I've seen the Google drive and it doesn't look good for Horner.
It may seem 'tame' but there are certain instances where he's telling her to delete the messages and 'offering her a way out' in leaving her job. She also asks him to stop on several occasions. Also, it just makes him look like a massive creep and a horny sex pest teenager. He's just weird.
For me, he has to go. If I was him I would walk before I was pushed.