This is an adult comedy Bollywood movie scheduled to release in the near future. +T-Series is marketing this movie heavily on social media. I imagine on
television too. The double standard here however is that they have the video publicly available on YouTube but they are blurring some cleavage shots. I am guessing they want kids to watch the trailer but want to stay inside the lines to prevent the video from getting marked as an adult video. If they had some shame, they would have marked it adult themselves.
The title of the meaning is also quite clever. It is a sequel to a movie named Masti (fun in this case the adult naughty type). Grand Masti is essentially naughty fun on a big scale. The problem is that Grand here refers to an human anatomy term in Hindi which has a slightly different spelling but they both sound awfully similar phonetically.