When someone I haven't talked to for more than a decade suddenly says "Hi" on my DMs. Feel ko it's going to be Pru-Life, Usana, or something along those lines... and most of the time I'm proven to be right.
People who are really, really, smile-ly and friendly. There's this overly-saccharine, it's almost fake, kind of person that I find kinda icky and sets off alarm bells in me.
Kind of like a Stepford smiler but with less overt eeriness, I guess? But I'm kind of referring to that, crossed with the person equivalent of a cake smothered in sugar and fondant.