link to amazon
Kindle comics in Japanese language
written and illustrated by Tsubame Kamogawa
An ordinary young man enters a high school and finds that two of his classmates are 25-years-old and 40-years-old crazy guys, and finds that they live same apartment. He gets involved in troubles caused by them.
This manga was quite popular when it was serialized in the comic magazine in 1977-1979, and amazingly, the comics are still published.