1. There's a guy who moves in with another guy and that guy starts to fall for him. And then one day, the guy who owns the apartment comes home from work and finds a girl with him, then he tells the guy to leave or else he'll do something 😉

2. in this one it's about 3 guys. One loves one of the other. But since he is shy, I guess, the other friend and helps him out. He drugs their friend and ties him up, then when he wakes up, he has sex with the initial friend. Then, blah blah blah, it turns into a threesome.

Extra: Is there any good yaoi with friends and threesomes? Just curious >< 😃

Story one sounds familiar, but I can't remember it either.

As for story two, it sounds like chapter 7 from Goshujinsama to Wanko, Triangle Love.

Another threesome story i've read that comes to mind is story one from Chotto ya Sotto ja Tomaranai. I'll come back once I remember any others. 🙂

Huum i don't know about the 2 manga titles, good luck with it. 🙂

Yaoi with threesome i remember:

Fallintrash
Kibishiku Aishite
Junk! Boys

Kimi Note ch7

I am not sure about the 2 yaoi titles you are looking for either, though both look like they would be really good. There are a couple yaoi that I recall have threesomes in them though -

Hard Core Heart
Peeping Tom - Oneshot

I think Kuurimii is right about Goshujinsama to Wanko, Triangle Love

Ikenai Otoko has a threesome that didn't make me feel icky. Rumble Rush and Himitsu no Kuchizuke by the same authors; the latter has a foursome 😲

Sex Therapist is also really good, not icky. Just one of the stories, but they are all good.

Some others:
Kaikan Fortune
King & Prince + Kaiser, ch 5 - very short but 😲
Oshioki Gakuen - more than a threesome 🤣

Groupie is all about a threesome between two brothers and a friend. Though I usually bow before NITTA Youka before whom I am not worry, in my opinion this is easily sensei's weakest work. The character that the two friends are in love with is flaming, and not at all like most of sensei's masculine men. Still, it's the longest work I know with a threesome the whole way through.

I really want to know the first story. I remember it quite well too, even what the characters say to each other, but I can't remember the name, ugh. It's bothering me! It's was one of those one-shots from a entire volume... 😢

I'm guessing the first manga you're looking for is Itazura Neko ni Goyoujin! It has the exact same opening plot as you explained. The second one I'm pretty sure is Koi Tomo.
Hope they're the right ones :$

Threesome yaoi, I've read A LOT 😀
These are some that I remember:
Mukizu ja Irarenee
Koi no Kawaki
Junk! Boys
Knock o 3-kai
Kibishiku Aishite
Child Epicurean
Giocatore, Hokaku Keikaku.
Hard Core Heart
Ikenai Otoko
Koisuru Omocha
Nigai Kajitsu
Nureru Karada (YAMAKAMI Riyu)
Oshioki Gakuen

I'll edit f I remember more 😛

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