NEON GREEN

-Shirou definitely has some instincts due to him being a clone of a demon, but because he lived around other clones with those same habut he thought it was normal.

- growls, hisses and chuffs a lot. Yuri found it endearing even though it would embarrass Shirou heavily. (He hissed at her when they first met and she asked if he was a cat)

- He would scruff both Yukio and Rin as babies, both because of maternal instincts kicking into overdrive but also cause rin was a wiggly baby.

- would use non verbal/instinctual language with Satan, not consciously but just because thats what felt right and because satan was more likely to listen. ( Yuri started copying him too).

- also used it on Rin and Yukio. Less chuffing and hissing, more purring at them to put them to bed and growling when they both where about to do something they shouldnt (combo move with the over the glasses glare)

- actually had rin and yukio sleep in his bed for years before they had their own room. And even then he never could get them in separate beds.

- Out of pure instinct neither of them slept in their own beds, always ending up on rins because his was(and still is) covered in blankets.

- both use non verbal/instinctual communication, half because both boys have difficulty with their speech(rin with pronunciations and yukio not being able to sometimes) and half because ot can come more naturally. Example would be rin chirping or yukio hissing.

- Rin fights the urge to groom yukio like a cat, shaking and frothing at the mouth kinda struggle. (Sometimes extends to the rest of the cram class too)

- yukio wears Shirous old coat, while rin wears his scarf. This is mostly cause Shirou wanted them to at least have some sort of item on them that said to other demons that 'these are my kids'. (Shirou is not immune to my creature blast)