A large and generically decorated Christmas tree sat centered in front of the school. A thin ring of charity presents was spread around the base. Among the bulk-purchased lights and tinsel, something else had moved in though.
Resembling nothing more than weird squashes on vines, the Bobbies had, within the space of a couple hours, spread over the whole tree. They were a rhizome organism, a rapacious alien pest plant, sweet smelling but a killer to crops. Luckily for the tree, it was dead. The lights didn't fare so well though: Where they touched the roots they were overtaken and broken. The tree showed signifigant dark patches and they were slowly but steadily growing towards the star at the top.
Naturally, Megumi Hisakawa called her Alien Party out.
But the piney depths of the tree concealed more than one type of alien...