http://www.mangago.me/read-manga/goshujinsama_to_wanko/
in chapter 7 are childhoodfreiends with flashbacks. it's only a oneshot and beware it's a threesome!
http://www.mangago.me/read-manga/ikemen_kun_to_saenai_kun/
http://www.mangago.me/read-manga/sukitte_iwasete/
http://www.mangago.me/read-manga/hello_again/
http://www.mangago.me/read-manga/hima_na_no_de_hajimete_mimasu/
http://www.mangago.me/read-manga/elektel_delusion/
http://www.mangago.me/read-manga/love_kids/
http://www.mangago.me/read-manga/mad_cinderella/
http://www.mangago.me/read-manga/baka_de_guzu_wa_daikirai/
http://www.mangago.me/read-manga/yume_musubi_koi_musubi/
... Ja Nai Kedo series
Yeah so I'm looking for some yaoi manga with the both of them being friends long ago, preferably with some flashback scenes where they were kids. It's so adorable (=・ω・=)