Essentially a filler episode with a brief cameo from Touma, the main protagonist of Index. Most of the episode revolves around Mikoto's roommate Kuroko and her attempts to seduce and possibly rape Mikoto, which are so over-the-top that they border on the yandere. Of course, each time Kuroko tries to make a move, Mikoto has brought over some friends to hang out, thus depriving Kuroko of her potential "one-month anniversary" time with Mikoto. On the other hand, they do throw in a partial Casablanca reference, and the dorm inspector lady briefly snaps Kuroko's neck for comedic effect.
Near the end of the episode, when Mikoto reveals that she bought Kuroko a present (a "USA" t-shirt) Kuroko accidentally drinks her own love potion to celebrate, then rips off Mikoto's undergarments with her teleportation powers. Mikoto shocks Kuroko in response with her own power, but it makes Kuroko even more turned on as the episode ends.