Merged contacts

I have an iPad 4th generation and I restored it to factory settings. When my wife set it back up, she was asked if she wanted to merge the contacts that were on there (my contacts) with her own, which she did. However, now that she had set the iPad up and signed in with her Apple ID, which is linked with her iPhone, she has my contacts mixed in with her own, on the iPad and her iPhone. Is there a way of deleting my contacts (other than deleting them individually) so that on both of these devices only her contacts show up?