Xemnas is a fake persona created by Walther III (the White Mongoose) to infiltrate the Xanathar guild.
Xemnas is a middle aged man with 2 estranged children and a wife he killed himself because she didnt do the laundry on time. After her death he found out he just didnt look hard enough.
Xemnas is 178cm tall and has a muscular build. If asked his favourite passtime is gossipping and hes in the Xanathar guild because he likes minotaurs slaughtering humans.

Xemnas is not real.