Not as...interesting...as most of these, but I was briefly involved with a guy I met online (3 months "together", though actually only saw him twice as we lived quite far apart and both lived with our parents at the time, he was 19, I was 16).
His spelling/grammar were absolutely appalling, really awful. There were certain words that he didn't seem to know existed, so he would say "as" instead of has for instance. First time he text, I thought it was a typo so let him off, but no, it continued. He called me "hunni", which I couldn't hack because of the spelling (though he probably thought that was the proper way to spell it) or princess (which just makes me cringe). He was constantly accusing me of seeing someone else (sometimes saying it in what could be seen a as a jokey way, but I could tell he was actually serious - first time he said it, I actually thought he was joking so jokingly replied "yeah, I've just been seeing my other boyfriend". He got sulky. Once he also accused me of fancying his brother - who I had never even seen - because he said his brother really liked the band Supertramp, and I, bored out of my mind, said "Oh cool".). He would also make AWFUL jokes ALL the time. I think part of it was nerves to begin with but it was so embarrassing, especially round my family/friends. I'm friends with him on Facebook and every other status seems to be some terrible joke. He would also say the most inappropriate stuff when were were alone which he obviously thought would turn me on but just made me want to slap him. Kissing him was like kissing a fish. I made my excuses for not letting him kiss me in the end, just let him kiss my neck...still most unpleasant.
The second time we were supposed to meet, I didn't really want too - mostly because after the first meet up, I realised I wasn't particularly interested in him (though our break up was technically initiated by him, followed two weeks later by the "I've made a mistake conversation", I did want to break up a while earlier, the only reason I didn't was because I was a bit worried about his mental state and was trying to think of the nicest way to do so) but also my grandmother was seriously ill and I didn't think it was fair on the family to have someone else around especially someone I didn't even want to see but he just wouldn't take no for an answer, and I was a young, shy, daft 16 year old so didn't just refuse to meet up with him.
For our first and last Valentines Day, he bought me a bottle of one of my favourite perfumes. It brought me out in a rash.
He once told me I was his "best friend" (pre meet up) and I thought that was quite sweet, replied "Really?" and he basically said yes, because he didn't have anyone else to be best friends with. Charming.
We didn't have sex (thankfully) but he did ask me once what he would need to do when we did - he has a kid now, so I guess he figured it out!
Finally...he once told me Avril Lavigne had to be rock because "there's electric guitars in it". No. Just, no.