Often, when a girl sees her boyfriend⋯ seeming⋯ like he's really enjoying fucking another woman⋯(Video 4 minutes 56 seconds.)

When a girl sees her boyfriend⋯ seeming⋯ like he's really enjoying "fucking another woman"⋯⋯

More or less⋯
She will feel a bit uncomfortable inside, a little jealous⋯.

Normal.

So I suggest,
「Tie the man up」.😜