What genocide are you talking about?! Read the fucking Book of Spells.
Globgor was a kid when Solaria (Hitler) started the war and she braged over how she genocided and torture monsters. Her excuse? The mewman race was superior (nazism and Nietzche philosophy)
When Globgor finally was at age to fight he would try to cause the less damage possible because Eclipsa told him so, and was even against attacking Solaria.
But, of course, he had to kill in order to protect his own soldiers and degend himself... using this propaganda to become ing.
When he finally had enough power and popularity he openly created a pro-peace movement to stop the war once and for all... through marriage.
The MHC (SS) ruined everything and Glossaryck has hated them ever since.