There's never a reason too petty to block someone.
Blocking (or, muting) is when you go onto someone's Wattpad profile, click the three dots at the top, and press "mute." The muted person can now no longer speak to you in any form: on your profile, in PM, or in books. They can't vote or comment on your stories, although they can still read them. Muting is a two-way street; you'll be unable to comment on their works or profile either. It's the only surefire way to ensure complete lack of communication between two parties.
(Although I have had a situation where I blocked someone and then later found them under a different username and was able to communicate with them again. I'm not sure if that's because they changed their username or what.)
If you feel the need to block someone, do it. There are no guidelines on who you should or shouldn't block. There's no line where blocking is just too petty. Wattpad guidelines suggest using blocking as a last resort, if you can't work out your differences with someone in the comments, but I disagree with that. If someone makes you uncomfortable, attacks you, or even just annoys you, go ahead and block them. Any time you want to never talk to a person again, go hit that mute button and free yourself.
Blocking isn't without consequences, and you definitely should think before you block. Do you really never want to speak to this person again? If the answer is no, you like them but they've done something offensive, try talking to them kindly about it. If the answer is yes, you never want to see their username in your notifications again, block 'em. Just go for it.
This is your space on the Internet. You get to choose who is allowed in it. Don't feel bad about cutting off contact with someone who is making you uncomfortable. They can survive. Don't worry about them judging you or harassing you - they can't harass you for blocking them once you've done it.
Blocking is always a viable option. Think before you block and consider your other options, but don't rule out blocking. It's an important tool that will help keep you safe on the Internet.
Don't ever feel guilty about blocking someone.
(Now all I need is the ability to freakin block tags)
