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About any Cellphone has Audio Recording functions. Not Video, which consumes lots of Phone Memory, but just Audio for Memos. Learn how to use it effortlessly to record long stretches of Audio-only.
Next time he pulls this malarkey, grab your Phone as though an unexpected Call came in. Walk away a few feet. Fake a Call. During this faked Call, start Recording Audio. Slip your Phone back into a Pocket or Smock Pouch; then turn around. The Mic is at the bottom of the Phone, so put it in a Pocket upside-down. Record. Without egging him on, get some good recorded 'Dirt'.
Make sure later the Recording is fairly audible, and clear. Use it as leverage in subsequent Discussions with Management. Or, see an Attorney. Settle for some Sexual Harassment Monies. Save another Gal from his Guano. In going up the Chain-of-Command, realize that the Company might sack you instead, seeing you as 'The Problem'. Fairly common...
'Don't get mad, get even' ~ Aerosmith
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