Ane-san Countdown!
姐さんカウントダウン!
Riko Umekita, a schoolgirl, finds her life disrupted when Saruwada-kun, the most intimidating boy in her class, takes her home. His family has a history in the Yakuza and is not to be trifled with. Upon arriving, she discovers her parents already present under unclear circumstances. Saruwada-kun then proposes marriage to her. The situation remains unexplained.