I want another story of this!! So kawaiiii!!! 😍

http://www.mangago.me/read-manga/ichido_dake_no_uta/

http://www.mangago.me/read-manga/mori_no_koe/ there's also this... not the same couple but sets related

Other story within the same world:
http://www.mangago.me/read-manga/itsuwari_no_mori/

http://www.mangago.me/read-manga/mori_no_kurashi/

http://www.mangago.me/read-manga/mori_ni_shizumu_tsuki/

It has a doujinshi too! http://www.mangago.me/read-manga/mori_no_koe_dj_nettai_no_mori/