Seeing as Kogasa and the rest of the UFO gang are stand-ins for the artist and others, I've added the artist_self-insert tag throughout, to match the Hang in There, Kogasa-san pool.
These guys were lying around on the ground of the open air bath.Wow, an open air bath!♡Drawing some old guy would be no fun so Kogasa-san's substituting.♡WmwmwmI've Gone to the Ōedo Hot Springs Story♥