I thought the same but I have 11 rabbits now, that's why I came to take the doubt
There are only 10 different ones defined in the game code. The gacha is a draw from only 13 choices, and 3 "Common" ones get 2 chances each, with the other 7 getting one chance each regardless of what rarity it says.
One says it's "Common" but it has only 1/13 chance, the one we're calling the glitch.