Invented brand name, suitable for a range of applications.
The name "killy" has only five letters and only two syllables. Two syllable names make popular global brands. Two syllable names are used by established brands like Pepsi, Lego and Sony.
Killy.com is a .com domain. Dot com domains are the most desirable top-level-domain in the world, famously used by websites like facebook.com. A .com is the first thing people think of when they think of a website.