The above post is completely irrelevant because pets do not help you in any way on this server, aside from looking neat. By posting his experience on another server, Takahara has made it much easier for this thread to fall into confusion and chaos.
1. You can't change the pet level.
2. Aside from wasting your money to get them loyal, pets do nothing special All they so is talk and make emotes from time to time when you get it to higher levels of affection.