Every once in seven days, ojou-sama's childhood friends―[Three-eyed Barnie Bloomfield] [Lamia Muir Head] and [Centaur Karen Bishop] came over to play.
On those days Malcolm-san became more psyched making the snacks.
The girls seem to often come over to play with ojou-sama who had become a hikikomori for years.
Not only Malcolm-san, but also Mercè-san, Gigi-san, Merry-san, and the other maids, at least as her servants, received them in high spirits as thanks for being ojou-sama's friends.