My ex's contacts appeared in my contact list

[Contactmystery]

I got a new Fairphone and used an app to transfer my contact list from an iPhone 4s. I can't find the name of the app, but it included me making a VCF file which was sent to my e-mail.

I gave the iPhone to my ex and now I have his contacts appearing in my contact list on my Android. It's just a smidge awkward to have his mum's contact on my phone and I'm a bit weirded out as to why this is happening. I know he had trouble logging out of my iCloud, but I can't imagine my iCloud and Android somehow synced up ()

Can anyone help with this?

P.S. No one apart from me has had any access to my Fairphone.

 

[Hadron]

You should be able to see what sort of contact "type" these are. If they are "Google" contacts then it suggests that your ex is syncing to a Google account that is also synced to your phone. If they are some other type of cloud service then likewise there is some account you are sharing. If they are phone-only contacts then they can only have got there when you imported the original VCF file. In any event you should be able to get a clue as to where they are coming from this way.