Hello, is there any way to delete account? Do I have to contact mods in that case?
Somebody will say that "just stop using it and logout forever", but I don't want to leave any trace of myself on this account, I want this to be erased forever.

I hate to be the bearer of bad news but accounts can't be deleted.

But why? Don't you guys have an access/log info to any account on the site/database? Or you just don't keep the information of registered users?

There is not a system in place to delete them.

Can they just freeze the account permanently? It's like banning them but as a request.

You can do that yourself.

Change the password to a randomly generated string, logout and don't save the password.

If your account is linked to an email, link it to a temporary email. Then do the password change.

Well some people couldn't pull the trigger so they ask someone else to do it for them(metaphor).

If you get banned here every IP you used to connect to the site gets banned, that's why banning is not an option for people that just want to get rid of their account.