Ch. 1 of Kuchibiru Tameiki Sakurairo http://www.mangago.me/read-manga/kuchibiru_tameiki_sakurairo/mf/v01/c001/
/☞/ Timeline for Nana and Hitomi's story: 1) Kuchibiru Tameiki Sakurairo - Ch. 1 & 6 2) Chocolate Kiss Kiss 3) Wishing on the Moon 4) Kuchibiru Tameiki Sakurairo (II)