RCT-740 - Public proposal while getting smashed for 1 million yen

Is it supposed to be a secret from their girlfriends? The first couple seemed to know each other, but I'm not sure. A public proposal while having sex in front of a crowd! If they succeed, they get 1 million yen for their wedding fund; if they get caught, they're out—but finishing inside is allowed! The 'if you get caught' part is so vague... it feels like the rules don't even matter anymore. Plus, if you actually did it openly in front of a crowd, you'd get arrested. There are even unexpected failures... (after all that sex). The filming is also done in a hidden-camera style, so the video quality is a bit lacking.