Mei receives a present from her father to help her cope with her sudden heartbreak... a robot boyfriend!?
(Source: Divine Sanctuary)

From ShoujoMagic:
1. 38°C
Taiji's normal body temperature is 38 degrees Celsius, or so he says, but Shiina thinks he's full of it. Taiji is a friend with whom Shiina can always--and does always--fight... Until Taiji unexpectedly confesses his love! Shiina begins to run a fever, but is that the only reason she's getting so hot...?

2. Solution Maze

3. Heaven in Jail

4. Winter's Aquarius

In the Taishou era, there was a girl named Kinako who loved to sing. However, her parents forbid her to sing, and forced her into an engagement! While running away from her engagement, she fainted. During the time she was unconscious, she traveled through time. She wakes up and finds herself in the modern age, where she is confronted by a group of rising idols?!
(Source: MangaUpdates)