Oh, hiiiii!
Oh, I remember! I'm extremely sorry for answering only now, lately I'm spending most of my energies studying for my next exam, that will be on Tuesday... the same day my Uni lessons will start, eh XDD

Sooooo, anyway... No, you aren't a liar for enjoying sexual stuff and seeming "pure" ^^
Each of us has different sides and you can't show to everyone your side interested in NSFW, especially with strangers or IRL friends unless you are close with them.
Outside I simply look like a very shy girl that doesn't wear skimpy clothes and is generally kind and doesn't talk about sex and stuff, while online... well, just look at my Twitter and Baraag! XDD
But also, seeming kind and cute and being interest in NSFW and kink aren't two opposite things! You can still be kind and look "pure" but also enjoy depraved stuff. There are artists that conceal and mix cuteness/"innocence" and perversion, there are people that are the kindest person on heart, that you would call naive and kind while they have the nastiest and most extreme kinks known on Earth XDD
So, don't feel ashamed to be a depraved kind person! It's completely fine and you aren't lying to others! Simply... some people wouldn't get it. Or maybe they would get it if you showed also that side, but it really really depends and I don't do that IRL, I prioritize my online stuff ^^
Each conversation and topic has its context, it's just... how it works. So don't feel guilty for it ^^

I hope this answer could help you! Sorry because it's late and sorry because it's messy!!!

Wishing you the best and giving you a comforting hug!! ^^