Junko's Ōji no Kikan (The Prince's Time) manga. Juné gave a tentative release schedule of late spring/summer 2

Kou Yoneda's Twittering Birds Never Fly's 3rd volume ships in February 2017

https://www.animenewsnetwork.com/news/2016-09-23/dmi-june-imprint-licenses-junko-oji-no-kikan-manga/.106794
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The one compiled volume also contains two other short stories about love between childhood friends. Taiyoh Tosho originally published the one compiled volume in May 2010.