Is there a yaoi threesome manga where they are actually in a relationship and not just sex...

Futari no Musuko ni Nerawarete Imasu

I've read hat one but thank youuuu

http://www.mangago.me/read-manga/uchi_wa_futago_de_teippai/
http://www.mangago.me/read-manga/koitomo_triangle/
http://www.mangago.me/read-manga/oboreru_triangle/
http://www.mangago.me/read-manga/sakaku_opera/
http://www.mangago.me/read-manga/docchi_ni_suru/
http://www.mangago.me/read-manga/futago_kareshi/

Thank you!!