After that run-in with her mother over the last couple of episodes, it's perhaps not all that surprisingly that Sasami wants to lock herself away from the rest of the world. However, it seems that she has a rather more substantial problem to deal with than even that.
With Tsurugi still missing, it's left to Kagami and Tama to try and deal with the fact that Sasami has used all of Amaterasu's powers to make herself unapproachable - something easier said than done when your friend is hell-bent on using those powers to strip off your clothes and make you into some kind of idol. Thankfully, Tsurugi makes her grand entrance just in time to assist in fighting the way through to Sasami, revealing the true mass of Sasami's weighty problem.
Rather than lying in the present, or indeed the pizza she ate the previous night, it's to the past we turn to look to resolve Sasami's current problem, introducing us to a younger Sasami long before her mother's death. As our present day Sasami watches on, her younger self contracts a curse which threatens all and sundry in the area including her mother - but is this really a view into Sasami's past? Perhaps not, given that she has no recollection of these events...
I suppose I should be used to elements of Sasami-san@Ganbaranai being a little confusing by this juncture, but even against that backdrop this week's episode feels a little too disjointed and messy to be particularly enjoyable - sure, I'm curious to see what it's trying to do so it deserves some credit for that, but there's not really enough to keep the story as it stands tethered to any central premise, an issue which stands out all the more thanks to the relative lack of comedy on show here.