He decides to do something daring while she sleeps. He further commends that "there will be a page or a couple of panels where the mood takes a sharp turn for the serious, and people confront the feelings that are at-hand. Archived from the original on May 12,
A Wish of my Sister - Wikipedia
The boy's mother takes him into the girls toilets to avoid any problems. There, Mizuki reveals that he is a boy.