How to remove Adsense Insert developers code

I needed something to insert adsense on my site, and based on a recommendation on wordpress.org, I got adsense insert. I never run it or configured it, but somehow it inserted the code of the developer on my site. I only activated the plugin. Nothing else. I then decided to delete the plugin but the ads remain. On my site there are two ads with the developers code. I emailed him, but no reply. The ads appear before the text on the post and pages and also wrapped around the text at the bottom of the post and pages.

Can anyone tell me where to go to delete the ad codes? I do understand that using the plugin meant you had to donate, but as I said, I never run it. It feels almost like malware on my site and I am very surprised that wordpress seems to have no problem with this plugin.