A dramatic video circulating online shows the man and the musicians standing downstairs while singing without the lady knowing.

However, they could see her through the glass window of her apartment on the first floor of a storey building engaging in serious sexual activity with another man.

In the video which has a Latino setting, the people are heard expressing disappointment at the lady’s conduct.

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Although the music band had already started singing to pave the way for the proposal, they had to abruptly stop singing after the disturbing discovery.

The video also shows the moment the lady, having heard the music downstairs, lifted the curtains to ascertain what was going on.

As soon as she spotted her boyfriend among the people standing downstairs through the glass window, she quickly closed the curtains.