Why is there always a line in Yaoi on how 'Forgive me, I'm at my limit' (⊙…⊙ )

It could be a Japanese thing we have no idea about! （￣へ￣）

Probably cultural /idiomatic thing, but probably mostly an excuse for losing control, esp in pseudo-rape yaoi.

I guess because he’s gonna lose control so he’s apologizing beforehand

I'm no expert but what I notice is that there's usually an expectation for the guys to be gentle in sex, and so I think the line is something like apologizing if they can't keep up that expectation anymore. Something like "I'm sorry if I lose control, I can't take it anymore it's too good" kinda thing

Oh the expectation is what I noticed from the few japanese people I met btw