Beware of the women that come up to you and ask you for a "date" when you are in Changi Village. The majority of them are actually Lady Boys (transvestites). The best thing to do is politely say no thank you and keep walking.
There are some transvestites at Changi Village at night, usually during the weekends and they like to hang around the carparks to look for potential clients. It should be OK as long as you do not approach or disturb them.