The protagonist is caught off guard when his in-laws suddenly make an unexpected request. The family was supposed to go on a hot spring trip together, but instead, he's asked to help his wife conceive—using the trip as an opportunity. Determined to remain abstinent until the trip, he struggles to suppress his growing desires. Unable to resist any longer, he heads to the hot springs and accidentally enters the women's bath. There, he unexpectedly catches sight of his alluring stepmother bathing. This unforeseen encounter profoundly shakes his resolve.