3P list?

What is 3p ?

Threesome sex, they tend to call it 3p in yaoi for some reason.

http://www.mangago.zone/read-manga/sefure_jijou_koibito_miman/uu/sefure_jijou_koibito_miman-chapter-1/1/
3P is threesome

idk a list.
but there are some :
http://www.mangago.zone/read-manga/sakaku_opera/
http://www.mangago.zone/read-manga/docchi_ni_suru/
http://www.mangago.zone/read-manga/choco_strawberry_vanilla/
http://www.mangago.zone/read-manga/bokura_no_mitsudomoe_sensou/
http://www.mangago.zone/read-manga/love_x_ero/

http://www.mangago.zone/people/tag/2337/3P%2B/

http://www.mangago.zone/read-manga/futari_no_musuko_ni_nerawarete_imasu/