Parameters

txt2img

anthro, furry, duo, 2boys, 2males, brothers, twins, bed, bedroom, cute face, shy, leg raised, precum, sex, anal sex, penetration, BREAK,
(young), teen, wolf, brown eyes, naked, sheath, canine penis, balls, anus, mouth open, BREAK,
(young), teen, wolf, blue eyes, naked, sheath, canine penis, balls, BREAK,
masterpiece, best quality, amazing quality, very aesthetic, high resolution, absurdres, depth of field, newest, scenery, ultra-detailed, detailed eyes, detailed fluffy fur, dynamic lighting, 8k, HDR, ultra-HD, highly detailed, HDR, realism, realistic, realistic lighting, caustic shadows,
Negative prompt: (worst quality, bad quality:1.2), lowres, low quality, bad male anatomy, bad female anatomy, grainy, noisy, render, filmgrain, text, deformed, disfigured, (female), (breasts), abs, extra fingers, bad anatomy, signature, patreon, web address, text, feral, blurry, faded, antique, muted colors, greyscale, boring colors, flat, bad photo, terrible 3D render, glitch, cross-eyed, lazy eye, ugly, distorted, glitched, lifeless, bad proportions, watermark, window, human penis, vagina,
Steps: 40, Sampler: Euler a, Schedule type: Karras, CFG scale: 5, Seed: 1454289852, Size: 1024x1024, Model hash: cab478b74a, Model: novaFurryXL_illustriousV100, freeu_enabled: True, freeu_b1: 1.01, freeu_b2: 1.02, freeu_s1: 0.99, freeu_s2: 0.95, freeu_start: 0, freeu_end: 1, Version: f2.0.1v1.10.1-previous-669-gdfdcbab6

img2img

anthro, furry, duo, 2boys, 2males, brothers, twins, bed, bedroom, cute face, shy, leg raised, precum, sex, anal sex, penetration, BREAK,
(young), teen, wolf, brown eyes, naked, sheath, canine penis, knot, balls, anus, mouth open, BREAK,
(young), teen, wolf, blue eyes, naked, sheath, canine penis, knot, balls, BREAK,
masterpiece, best quality, amazing quality, very aesthetic, high resolution, absurdres, depth of field, newest, scenery, ultra-detailed, detailed eyes, detailed fluffy fur, dynamic lighting, 8k, HDR, ultra-HD, highly detailed, HDR, realism, realistic, realistic lighting, caustic shadows,
Negative prompt: (worst quality, bad quality:1.2), lowres, low quality, bad male anatomy, bad female anatomy, grainy, noisy, render, filmgrain, text, deformed, disfigured, (female), (breasts), abs, extra fingers, bad anatomy, signature, patreon, web address, text, feral, blurry, faded, antique, muted colors, greyscale, boring colors, flat, bad photo, terrible 3D render, glitch, cross-eyed, lazy eye, ugly, distorted, glitched, lifeless, bad proportions, watermark, window, human penis, vagina,
Steps: 40, Sampler: DPM++ 3M SDE, Schedule type: Karras, CFG scale: 5, Seed: 1202883170, Size: 2048x2048, Model hash: cab478b74a, Model: novaFurryXL_illustriousV100, Denoising strength: 0.45, freeu_enabled: True, freeu_b1: 1.01, freeu_b2: 1.02, freeu_s1: 0.99, freeu_s2: 0.95, freeu_start: 0, freeu_end: 1, Version: f2.0.1v1.10.1-previous-669-gdfdcbab6


Then a lot of small colorings in Paint.NET, edits, clips, inpaintings, etc. Followed by upscale: 

postprocessing

Postprocess upscale by: 1.4, Postprocess upscaler: 8xNMKDSuperscale_150000G