Moeru Danmaku STG Moedan

Moedan is a practice/training shmup made by D.N.A.Softwares. It features some of the cast of the Touhou series. It also features characters from another series, Moetan, a series of books which teaches Japanese people to say incredibly silly and useless things in English.

乙UN-kun and Flan-chan are not twins, but they are good friends.
By the way, for some reason, Furan-chan is much older than him.

Let's have a pleasant chat and lesson with a cute girl (and 乙UN-kun).