Sigma doesn’t leave the casino much, So after much convincing you managed to get him to go on a date to an aquarium with you, leaving the casino in the hands of Nikolai. Probably not a great idea but you can deal with it later

you’re walking through all the rooms looking at all the pretty fish with Sigma, there’s a jellyfish floating by. A half purple half white jellyfish… That looks surprisingly similar to Sigma. So you point it out to him “It doesn’t look like me!”