Anal Masturbation- Can it cause damage?

This is embarrassing and I can't even say it's for a friend because no one will believe me xD But it is true! Okay, so she's a girl too and a virgin but she masturbates. The only way she can get an orgasm is by stimulating her clit and her anus at the same time. The thing is she's really scared that she could do her body damage by stimulating her clit, vagina or anus. She uses an electronic toothbrush on her clit and index to middle finger on her anus. Is there any way she could be hurting herself?