Essencialy the BotPet is a Bot character that you can command and to things like express emotions as a normal player, level on spots etc, and the best part of it is that it's completely free.
There are 2 types of BotPets: Normal BotPets and VIP BotPets (only for VIP players)
Yes, they can attcak mobs on spots, help you level up and theirselves, use different skills BUT REMEMBER THEY CAN DIE!
Bot Pets are limited to only 1 per account so be careful what you create, because it can take on any character type class. To create another one the BotPet has to die first.