Glitch (?)
I am not sure if anyone knows this but I'll share it anyways! I just found out about this today. So it turns out that if you use the packet spammer and summon the pinkomancer skeleton, you can use your Necromancer class and the pink skeleton will still attack for you (even though it's pink and not the usual undead skeleton you see). I just thought that it is kind of cool and it was worth sharing!
nah, you can summon any pet with the packet spammer even darkside wolf.
Yes, they can see it and probably will ask how you have the pet equipped but don't have the class on your bag...