Based on a harem romcom manga written by Nakamura Rikito and illustrated by Nozawa Yukiko.
In one Humorous Chapter of the Manga, Rentaro somewhat shamelessly Plugs the Manga's Merch line by wearing Various character Buttons of his Girlfriend all over his Body. During Production of the Anime, Rentaro's Voice Actor Wataru Kato recreated this Outfit.
The series premiered during the same time as the Second Season of Girlfriend, Girlfriend; another show that begins with the Main Character asking 2 Girls to allow him to date both of them at the same time & slowly gains more Love Interests over time.