CW // incest, shibari/kinbaku, a/b/o, a!Sukuna, a!Ryoumen, o!Yuuji, breeding, spit, biting/marking, blood, technically a Yakuza au
Summary: Yuuji learns kinbaku/shibari (sorry idk the proper terminology) from Megumi and convinces Suku-nii to let him try it on him. Suku-nii might have some regrets......