yaoi. they were having sex and the other already inserted it but the bottom said "hurry up and insert it" bcs hes dick too small.
Someone said before that it was this:
https://www.mangago.zone/read-manga/not_a_sugar_daddy/
wholesome bl story with no sex scenes included geez #-.-)
I haven't read that many BLs, so the only one I've read that immediately comes to mind is Star x Fanboy (박배우 x 김남팬), though you might've already read it considering its popularity. It's a personal favorite and one of my comfort series. I've also heard that Heartstopper (which you can find on the WEBTOON app) is great, though I haven't gotten around to reading it yet. I'm fairly certain Heesu in Class 2 and A Guy Like You are also SFW, but if you're looking for a more wholesome vibe I'd definitely recommend Heesu in Class 2 out of both of them (they're both popular as well so you might've already read them). You can probably find more through the shounen ai tag, which is usually used for SFW stories. But, as you probably already know, you should look out for the yaoi tag just in case (or see if the comments mention sex scenes).
Sorry if I wasn't of any help. I'm not well versed in the topic of BL but I wanted to try helping.

I dont remember much but it started off with a girl with a blue outfit? her badongkers showing offand then he bumped with this really tall handsome buff guy. they end up hitting it off because the man thinks hes dreaming or smthing. then a white mark appeared on the girls tummy