Lowkey Harley Quinn. For a while Annie but I finally watched Titan so that's out. xP And pretty much any character played by Helena, Lara, or Lana that I haven't seen yet lol.

I've actually been guilty of these a couple times. While I dont like her anymore, In the 6th grade I was obsseaed with Lola Bunny even though I've never seen Space Jam. I also was really into the comic book version of Blackfire (I still am) even though I never read the comics. Now there's Arima Kishou who I'm invested in even though I don't plan on watching TG.

Don't think so.
I like some characters whose series I haven't seen but I wouldn't go as far to say 'really invested'.

It doesn't make sense. What if the character you so called got invested with is beyond annoying. I won't ever do that honestly.

izaya! with all the people saying he is awesome,i started liking him... for him i started watching durarara.... i really turned out to be an awesome character... along with him started liking shizou too! ^^