I don't get much comments, positive or negative, but I think somewhat meanest comments on my comics have been for example commenting on the protagonist Sir Kiljaos the lion paladin:"Why he looks like a bootleg Simba?". I've never been too offended about this and just find it funny because he indeed did look too much like Simba from The Lion King in the early comics and drawings (below are comparisons between his looks in 2012 to 2019). 


Once my brother also commented on why most characters have to be anthro animals, but he just doesn't understand fantasy things and isn't the target audience so I've never been that offended by this.
Otherwise really the meanest reactions to my comics so far have been some times when I've shared a new page at Discord groups, and everyone have just ignored it and have immetiadedly started talking about something non-related after my posting.