[TOMT] [Song] French song, something like "Desiré", more info INSIDE!

It was a opera or something like that, or a musical. It was something about art, you know.

A guy was singing, it was on YouTube I guess. The guy wore a "yoga pants" kinda thing, it was white I believe.

I couldn't find it after 5-6 years, please help me guys!!!!

Desiré...