Yesterday we introduced you to the sweet, petite Shannon twins, Karissa and Kristina, who will most likely be taking over for the original Girls Next Door and becoming Playboy founder Hugh Hefner's main squeezes.

But something we didn't know yesterday was that these identical eyefuls really ARE double trouble!

New reports reveal that the blondes with the bite-sized boobs have charges of felony aggravated battery on their records. According to TMZ:

Turns out Hef's 19-year-old handpicked twin successors to the throne of Holly, Bridget and Kendra come with a checkered past. Karissa (left) and Kristina Shannon (right) -- who have recently moved into the Playboy Mansion -- were both busted by St. Petersburg, Fla. police for felony aggravated battery back in January. They both received probation and were ordered to pay restitution to the two victims.

Karissa also has a misdemeanor battery charge on her record from 2007. Atta girl!

Playboy had no comment.

UPDATE 6:40 PM PT: We just talked to a relative of one of the victims and here's what they tell us went down. The twins went out after work with one of their Wing House co-workers, Erica Civello, to a house party. Kristina allegedly started arguing with Erica, and Karissa came up behind her and hit Erica over the head with a bottle of beer and they both "jumped her." Erica suffered a concussion.

Sounds like Hef is going to have his hands full with more than just the Shannons' little handfuls.