My wife bought me some y underwear and T-Back trunks for my birthday. In fact, what does she want ?

Every weekend, She requested me to wear rhose T-back swimming trunks at home (Well, we don't have children ) . Sometimes she asked me to dress up like a pilot , personal trainer and fireman. ( She takes those initiative to buy those dressings for me ) . I am happy that she says I have a nice-looking body . But what is her intention of doing this ?