UK usage: Cakey, tending to be over-sweet in demeanor, and even when genuine can seem to be playing to everyones good side to be popular (trying to be everyones best friend without having earned that respect or loyalty). Can seem naive and ungrounded in constant fascination with what are essentially trivial issues and irrelevant concerns. Doesn't often 'get it' socially.
Tiffany was Cakey, she had the ability to be nice, but expected too much when she asked favours of people she barely knew. Anyone who wanted her, she would play for favours until they didn't care and then she would wonder why they were off with her, when they realised she wasn't interested in them. She didn't connect or think deeply enough to realise others peoples feelings hurt them for more than the glancing blows her ego ever took, she just ignored them to make herself feel better. Everyone was best friends forever or she didn't care at all.