I think my personal Tumblr lolcow is saphirafoxgirlspost.
A bit of a change up from the normal variety to come from Tumblr, she's your run-of-the-mill 13 year old roleplayer at first glance. Except she's in her mid twenties. If she had a main account I'd use that one instead but I'm pretty sure this is her only account, and it's basically a main anyway since she whinges on about personal life and feelings enough on it.
A few friends and I managed to get her into a Skype chat and talking with her out of character is exactly like trying to talk to her in character: she acts like an insufferable anime girl/furry. Normally I'd chalk this up to her maybe being autistic, but she said outright that she doesn't have any developmental disabilities or mental illnesses in one of the moments she decided to string a normal sentence together. (Note: this was a bit before Tumblr decided that having mental illnesses was cool.)
We also had to suggest multiple times that she make a rules page, as well as mark her blog as NSFW due to all the (badly written) smut rps, before she actually did it.
(Also, a specific instance that made me chuckle at the time and continues to this day: she got a question on her blog asking her character's cup size.
This was her response, implying she really, REALLY doesn't know how bras work. I would joke and say her character is an inflation fetish, but she had once stated on her old blog -- now sadly deleted -- that Saphira looked like her only skinnier.)
And yeah, there are a lot of SJWs and the like that are pretty ridiculous, but I haven't found one yet that's so incredibly thick as Saphira.