let me leave a comment to also research later
Chika-chan to! Has the sandwiching thing I believe, though I may be wrong.
https://www.mangago.zone/read-manga/yokohama_3p/ (Oneshot)
https://www.mangago.zone/read-manga/harami_bara/ (Ok… this is 4p and they do that in ch.5 but it’s the fuckin weirdest & clingiest yaoi stories that I’ve ever read)
Thank you! Now I can finally complete my *cough* research *cough*
LMAO i died when reading harami bara. I can't even read it seriously. That blondie's ass sure is something huh
3p bls where they do the 'sandwich'ing