First off, welcome to the KHR Imagine World! may you be blessed with many followers :D Can you do possesive headcanons/scenarios with Yamamoto, Hibari and Ryohei?
If another guy comes up to his s/o, he has the tendency to wrap his arm around them tightly. But he has that same smile towards the guy, laughing and talking all the same.
The one time he really showed true bitterly cute possessiveness was during one of his practices. His s/o was watching from the bleachers when one of their male classmates took it upon himself to sit next to them. He saw the two talking, and suddenly a baseball came flying and smashed against the fencing in front of them. The boy jumped out of his skin, and there stood Yamamoto in the distance, smiling like nothing happened.
Hibari is low-key about his possessive tendencies. You wouldn’t expect it until it actually happens.
He has a list of names and backgrounds of any other guys who have a close connection with his s/o. Nobody knows this.
Sometimes if his s/o has plans Hibari will literally steal them out of nowhere— As in, literally show up out of the shadows and take them away so he can have them all to himself.
He’s got it in his head that he can fight anybody who thinks they can just snatch up his s/o
He always needs to have his hands on them. He’ll often lean on their shoulders, or stand behind his s/o with arms extended past their shoulders like they’re some cute armrest.
Often stands taller when around other guys when with his s/o. Some kind of dominance thing, perhaps.