Sekai wa Bokura no Tameni!

From Midnight Scans:

Ogawa Maho is a young, fresh teacher who just arrived in Tokyo to take on a new teaching position at a high school there. Things don’t go as she planned, however, when she breaks up with her boyfriend whom she had been dating for 6 years. Distraught over her breakup, Maho has a one-night stand with a guy she meets on the street. The encounter was memorable and manages to cheer Maho up enough so that she can face her new job and move on with her life. Of course she is shocked when she discovers that the random guy she spent the night with happens to be one of the students in her new class!

Contains the following one shots:
ch. 4: Currently Indulging In Love
Fukami Tadashi-san's twin brother, Katsura (who's nothing like his brother), has already investigated his brother's date and he has decided she is inappropriate for him. They break it off, but Tadashi is depressed so Katsura finds her again and begs her to get back together with his brother. What's going to happen?

ch. 4.5: Come Over To My House (Christmas Special)
Akiyama Riho's parents have passed away and she is currently living with the Suga family. She is dating the second son of the family but her love life there is full of obstacles..

ch. 9: Touching Lies With Lips
Nishihara Kimi's father is accused and arrested for a crime he did not do. She goes looking for a lawyer and Ehara Shirou, her ex-boyfriend, is the one she finds most capable to handle the case. He is an expensive lawyer but she's willing to do anything...

ch. 10 (not translated): I won't let you sleep tonight!