This is a short anime episode set during the events of Grisaia no Kajitsu. In the episode, Sachi Komine helps Yuuji take a bath, saying that it is a maid's duty to help others.
It is unknown about what time this takes place during the anime, whether it takes place before or after Yuuji helps Sachi with her problems.
- *spoiler*. Although Sachi knew Yuuji before he came to the school, as kids, she may not have liked him so far as to get into the bath with him, leading us to assume that this takes place after the 7th episode.