Tengen Toppa Gurren Lagann Easter Egg - Diebuster Reference

In episode 6, you b******s put us in hot water, look closely at the girls in the bath house. one will have long pink hair, and another short, silver hair, a slight tan, and something on her forehead. this is a reference to Diebuster, released about a year earlier, by the same studio, Gainax. the girls are the two central characters, Nono and Lal'C Melk Mark.