My personal favourite character has to be Morgana. Powers aside, this four-winged witch of darkness is quite cute once you get to know her. I always have a soft spot for temptress-like villainesses, so Morgana really captivated me when I took her for a spin in LoL.

Other than that, I also like Kha'zix purely because of that menacing design. If anything, I'm more scared of how he looks more than how his abilities upgrade every time you upgrade his Ult...

And finally, as another honourable mention, I have to give a spot to Talon, purely because of how much he reminds me of Ezio Auditore from the Assassin's Creed franchise.

5925623 Kled, for the sheer fact that the nuttier-than-squirrel-pie lines he constantly spouts make people like Jinx look sane.
Also Tahm Kench because A: he's voiced by the legendary Pat Duke (I can't watch swamp people anymore without thinking that Tahm's lurking in the water nearby, narrating what he sees). B: he looks like one classy Cajun catfish. And C: We love how his origins are a creative and quite original concept, as well as his classic 'deal with the devil' shtick.

5925623 Fan of Talon and Vel'koz. I for one am a complete fan for anything that's an assassin's creed reference and Vel'koz's lack of morals for the pursuit of learning and science gives him a special place in my heart.
I mean knowledge through disintegration? Sounds like a good way to study for exams
EDIT: Huge nerd over Cho'gath too. I go through a lot of mains so I have too many champions with positive experiences.

Nasus He was the very first champion I picked up and purely because I didn't understand the game and I wanted the big doggy (good thing it worked out). Amazing lore, his voice is so awesome to listen to and I love his quotes, and he's an absolute joy to play. So laidback, farm top and last hit _everything_ within five feet of you while everyone else screams at each other, occasionally wandering elsewhere to use your epic slow to help gank--then the 20 minute mark comes around and you get to body block for your carries, then get back the health you lost by leisurely jogging after a hobbled squishy and oneshotting them.
My only complaint about Nasus is, of course, his lack of extra content; he's a classic champion who has the more limited set of voice lines, and his skins are all kind of…meh. Although the Worldbreaker splash art looks _epic_ admittedly, but the skin itself is mediocre.

Aside from Nasus…I also love Warwick, especially since his update; they really did a good job with him. Story- and concept-wise, Jhin is pretty cool. For pure aesthetic, Kindred and Aurelion Sol are epic. For just gameplay, Thresh and Tahm Kench have the most fun abilities. I don't have much of an opinion on the new love birds yet, but Rakan looks like he has a fun personality.

I like Kayle. She's dutybound, straightforward yet has the slight implications that everything isn't on the up and up. Mostly in her reasoning of why she wears her helmet. Her abilities and this knowledge of her seeing war/conflict as ugly paints an interesting character.

Jax is my main man. I like that he's such a fucking badass that special rules had to be implemented just for him, which did nothing at all in the end to curb his awesomeness. Also, all the mistery that is behind him and those tied to him. Just who or what the hell is him anyways.

Also, best drinking buddy of Gragas.

If I had to pick one Draven I just love the charisma he has for himself. But a close second is Vladimir with his Marquise skin he looks like Dio Brando so that's a plus.

I like Fiddlesticks, he's straight-up creepy and has a talent for scarying people. He kinda looks like the grim reaper.

5925623
My personal favorite is a three-way tie between Kindred, Evelynn, and Jhin. Kindred due to the fact that Lamb and Wolf are the most unique and fascinating portrayal of death incarnate that I've ever seen in my life, Evelynn due to the lewd and the sheer bliss and horror that she can bring, and Jhin due to him being the absolute best character of all in League Of Legends and being the game's masterpiece.