Or rather, Santa may have learnt space/boundaries manipulation from Yukari and taught Sakuya about how to stop time.
Not Satan, Santa.Oh? Santa-san is a good youkai!Such a fierce youkai, but I can't reject him...!Everyone is equal!Santa?Santa-san delivers presents to all the good children.As I was saying, he's not a youkai!Santa-sanChristmas is when Santa-san comes by.He does that for the good children!