Ep. 1: Yotsugi Ononoki infiltrates the Araragi residence while Tsukihi is away

1

Yotsugi Ononoki has been secretly staying at the Araragi residence to monitor Tsukihi Araragi. During the day, while Tsukihi attends school, Yotsugi takes advantage of the opportunity to spend her time freely within the house. However, her presence is not entirely unnoticed. Tsukihi unexpectedly returns home earlier than anticipated, leading to a direct encounter with the intruder. This sudden return disrupts Yotsugi's routine and brings her surveillance activities into the open, creating an immediate confrontation between the two characters within the domestic setting.