At their feet, standing atop it. The idea is like if we show the top half of the pic they just look like a cute couple and then full pic OH WHOA WAIT WHAT.

And I don't have any specific references for the outfits! Have some fun with it, they could go full formal wear or they could be in cute casual clothes or business clothes or school uniforms. As long as it's white and pure like their love for each other~