its very easy to assume that about rin but the more you understand and read into his character you realize all this possessiveness, obsession and rage is born out of an ardent need for his brother’s validation. You can see this at the end of u20 match where sae gives him a shred of attention (mind you he was not even looking at rins face while talking) and rin’s whole fucking facade crumbles down and he goes back to the cute sweet little boy that he really is since childhood. I’d say it would be ooc for rin to be the domineering violent “top” towards sae because he never was one. Anyone who goes “🥺🥺🥺🥺 nii chan” wants to be stuffed like a thanksgiving turkey by their older sibling im sorry anon