A boy who is entirely controlled by a girl and has no free will.
He has to do whatever the girl in control says.
Person A: "Where is Bennie, will he join us?"
Person B: "No, his girlfriend doesn't let him, he controls her"
Person A: "He should be called YuukiSena instead of Bennie"
You call someone YuukiSena, when he is getting controlled from a girl.
A submissive boy.
"Come play League of Legends with us"
"No, I can't - I'm doing something with her"
"What a YuukiSena!"
Someone who is "thicc" and "fit" at the same time.
"Look at that girl, she THICT"
A virgin or someone who is 13 years old
"Did he ever have sex?"
"No, he is a Ninja Sub"
"Oooh, that explains everything"
"I can't hold it back anymore, the simptation is too strong"