The lonesome struggles of the only living being on Earth.

Ono Matori is a high school student who is secretly a successful erotic manga author. He has recently found new inspiration for his work from his neighbors and classmates, the Hikasayama twins, Haruna and Wakana. Both Haruna, the cheerful and active half, and Wakana, the cool and collect one, both fall in love with Matori. He unwittingly agrees to date both of them both for research purposes and personal interest. Their love triangle will help Matori with his erotic manga storyline but how will his life change back in the real world?
(Source: MangaHelpers)

In the year 20XX, the decline in birth rates is a serious problem. To counter this, the government has established an outrageous academy. The academy's goal: "To teach boys and girls how to properly date, and in the near-future create good families through marriage." In a school where the doctrine of "love" has gotten out of hand unfolds the ultimate love battle of two virgins!

(Source: MU)

A short, coming-of-age story of a middle school student named Yu. From the mangaka of Scum's Wish.

Seventeen-year-old Mugi Awaya and Hanabi Yasuraoka appear to be the ideal couple. They are both pretty popular, and they seem to suit each other well. However, outsiders don't know of the secret they share. Both Mugi and Hanabi have hopeless crushes on someone else, and they are only dating each other to soothe their loneliness. Mugi is in love with Akane Minagawa, a young teacher who used to be his home tutor. Hanabi is also in love with a teacher, a young man who has been a family friend since she was little. In each other, they find a place where they can grieve for the ones they cannot have, and they share physical intimacy driven by loneliness. Will things stay like this for them forever?

(Source: MangaHelpers)

Included one-shots:
Volume 1: Nyan Nyan Prelude
Volume 2: Nyan Nyan Serenade
Volume 3: Nyan Nyan Oratorio
Volume 4: Nyan Nyan Cantata
Volume 5: Nyan Nyan Andante