Sailor Moon
Protect Mamoru: Ninja Usagi's Jealousy
S4 E9:
A small fire incident leaves Mamoru's apartment in a total mess, forcing him to stay at Rei's place for the time being. Unhappy that her boyfriend is staying at another girl's place, Usagi decides to stake out Hikawa Shrine dressed in a ninja outfit to make sure nothing happens between Mamoru and Rei.