Riiko must deal with a miniature version of Night while his full-size body is in the shop for repairs, and he is in for a full-sized battle for Riiko's affections when Soshi tries to move in.
Riiko races to the apartment of Hidemi, the woman who has kissed Night, to keep them from sleeping together, which would imprint him and take him away from Riiko forever.
Shy Riiko Izawa signs up for a free trial of a mysterious Nightly Lover "figure" and finds a cute naked guy standing on her doorstep the next day who wants to be her boyfriend, provided Riiko can pay the fee.