The devil from below
From Love-shy.com wiki: A wiki for the dating-challenged
The devil from below is a persona exhibited by a condescending newcomer on the love-shy.com forums who believes that he knows the solution to love-shyness and incel, and that his opinions take precedence over that of the forum as a whole due to his having sexual experience.
Occasionally, pick-up artists or otherwise sexually successful people will join and post on the love-shy forums. They will offer their theories on why everyone on the forum is incel or love-shy, often making highly inaccurate, even insulting generalizations. Despite the fact that they quickly discredit themselves, they believe their word to be gospel, as the word of the less sexually experienced members is irrelevant to them.
The devil from below usually becomes impatient with the fact that the forum will have none of his commandeering nonsense. He will usually storm off in short order, never to be seen again. He is usually a bad influence, because he confirms love-shy and incel fears of the sexually experienced not understanding or even treating them as second-class citizens. In truth, moderate, non-condescending opinions of sexually experienced people could help love-shys and incels improve themselves.