Yusuke has always been scared of women due to an incident from childhood. when the twins who caused this fear move in with him, his problems only intensify because both girls have had feelings for him since their first meeting, where he saved them from a dog. despite their love for him, yusuke's phobia makes their affections little helpful to him now compared to when he was young. his days of suffering are back.
1+2=Paradise met with the same problems as U-Jins Angel. Because of that Kodanshas shonen version only has 4 volumes and was incomplete until Shobunkan completed the last fifth volume, republishing the series labeled as an adult manga instead of shonen, but with no real difference in the content.(Source: MU)