Kilo is a 125ft fall giant-sized red fox with two tails with a pretty normal red fox fur pattern. Red fur on most of his body with black fur on the tips of his ears, and upper part of his arms and legs. White fur on his chest, muzzle, tail tips, inside of ears, and lower part of his feetpaws (including the areas near his claws). He also has brown eyes, brown hairfur. He normally wears just a blue hoodie or t-shirt, and a thick adult diaper. He was born, raised and lived his entire life as a macro.
The island that Kilo was born on is called Macratan Island. Not much is known about this mysterious island, which was discovered only about 15 years before Kilo was born, outside of everything being extremely large, around 20 times larger than their off-island counterparts. Everything native to the island such as plants, fruits, and native furs and humans living on the island were all this huge size. The residents of the island had no modern technology according to researchers studying the island, and the natives lived in huts and kept their newborns in the safest part of the island, which is a tall hill away from the forests.
Sadly, only afew weeks after Kilo was born, a wildfire began to devastate the island, which ended up sadly destroying the vast majority of the plant life and killing almost all of natives who made their home in the giant forests. Kilo suspects this also included his parents. Luckily, there was a research ship that was nearby trying to study the island. They saw the wildfire and instantly began to attempt to rescue any living creatures that they could. However, by the time they could arrive on the island, the wildfires have already destroyed most of the island. The newborn macros were sadly the only ones the researchers could save due to its safe place outside the forests of the island kept it away from the fires. They used helicopters, several nearby boats, and any other equipment at hand to save the newborn cubs and babies from the island. This of course included the newborn Kilo.
After rescuing all these newborns from the devastated island, the researchers quickly created a plan to give the cubs to orphanages and foster homes where they could be raised as normal, although huge, cubs. Many agreed to take on the task and challenge of raising a macro cub or baby, and macros began to be raised all across the world.
However, for Kilo cubhood was anything but normal but being a macro, that was always suspected to happen. As they grew up, some of the other young rescued macros started to get known for being destructive behavior and began "rampaging" towns, eating people, stomping on people etc. As news of these destructive macros started to spread, Kilo sadly was quickly shunned by everyone in the nearby town as they were afraid he too would end up like those other macro kids. 
Kilo however was nothing like those other macro kids and was, and still is, extremely kind and gentle and he always wanted to make friends and have the normal sized kids play with him. Sadly, even though the orphanage owner who took Kilo in tried to tell the town about his kind and gentle nature, it took a very long time for any kids and especially the townsfolk to see him as anything but a potential monster waiting to rampage their town. This lead to Kilo being very lonely the first several years of his cubhood. He usually played simple games he could play by himself, such as marbles (which were actually bowling balls that the orphanage owner gave him). This started to made Kilo quite shy and kind of sad after awhile, as he just figured that everyone was afraid of him for what he was. This did leave a scar on him that still with him as an adult, as he still gets nervous about other’s possibly fearing him just for his size.
Though later in his cubhood, especially after 9 years old, the kids and town slowly stopped seeing him as a potential monster and began to see his kind and loving nature. Once they met Kilo, they quickly warmed up to the kind and gentle giant fox, they began to quickly made friends with him. Kids started playing with him, and they especially had fun climbing him and swinging on his always moving tails. The townsfolk began to ask him to help out with tasks like construction and moving cargo around the city, which Kilo was always happy to do and still does to this day.
How Kilo came to be incontinent (and came to have to wear the thick diaper he's openly sporting) was when he was a 3 year old cub, he was playing marble near a cliffs edge. As he was playing, the cliff was beginning to slowly crumble from the giant cubs weight. It eventually gave way, which made the poor giant fox cub fall 160ft (equivalent of a 30ft fall) down on a large bolder, landing sideways on his torso. This broke a portion of his pelvis, and the fragments of this broken bone caused some internal damage, and severed the nerve to his bladder. Despite his huge size, a team of doctors were able to do surgery on 3 year old Kilo and were able to repair the damage the bone fragments caused (mainly cuts to internal organs) and bandaged him up with more medical bandaging than the doctors ever seen in their lives. Within about 2 months, the giant cub was back to his normal, playful self. However, the nerve damage to his bladder was permanent. This meant that Kilo now had full urinary incontinence and had to wear diapers all his life. 
Ever since Kilo was brought into the orphanage, a crane was kept near the orphanage for using to change Kilo's macro-sized diapers. They were supposed to return it once he was potty trained, but due to the accident, the town was allowed to keep the crane. Kilo though learned to change his own diapers around age 8 or so. However, the town still has the crane around today just incase they offer to change his diapers.
At first, he didn't like wearing them as thought he would be made fun of. Though, as he grew up (especially during and after his teen years) he grew to really enjoy wearing diapers and began to have no problem wearing them in the open. The diapers he's always worn are made for Macratans are up-scaled to be proportionally the same design and thickness they are for normal-sized furs. He's lately has been the mascot on some diapers brands selling to macros, such as Mythies Macro.
Kilo was also born with two tails. Kilo, as well as everyone else who knew him, just suspected this was a birth defect that had no negative effects and didn't think much of it. However, he had some blood work taken just before his 18th birthday as part of a checkup on the heath of all rescued macros. Once they did DNA tests on his sample, they showed he is also half "kitsune" (NOTE: Kitsune means fox in Japanese, this term is used outside of Japan to refer to fox-spirits of Asian mythology). Kitsunes are a type of fox-fur native to Japan who have have a heavy mythology in Japan of having powers such as emitting fire, changing form among other things. Once this was reported to him, Kilo was quite intrigued to learn he was half-kitsune. However, he is unsure if he can do any of the abilities kitsune's are capable of doing in mythology. The researchers who did the DNA test are just baffled on how a macro and a kitsune (who was supposedly normal sized) could even mate, but his DNA shows he's a obvious clear mix of the two.
Kilo now lives in a macro-sized home outside of the town he was raised in. His home was built by him and many of the townsfolk who were happy to help. His giant-sized home has all the typical amenities of a normal home, such as a kitchen (though they had to have a giant refrigerator and stove specially made for him), a living room (which has a large projector for his TV), a bed room, a bathroom (which has no toilet as Kilo doesn't need it), and a guest bedroom for normal sized people. 
He still continues to help out the townspeople when he can with tasks such as moving large cargo, with certain construction tasks, and sometimes even rescue in high-rise buildings. In return, the townsfolk help provide him with his needs such as food (usually very large quantities of normal sized food, as well as full large fish such as tuna), the diapers he needs to wear, etc.