Inspiration to support the fandom of Kanda Yuu and Allen Walker from the anime/manga, D. Gray-Man.
Compound word of Yullen (Yuu + Allen) and Inspiration.
Also used as,
1. NUUU, I need more YULLENSPIRATION!
2. I think this just gave me some Yullenspiration.
3. I got Yullenspirated from the new chapter of DGM, when Kanda and Allen fought that Lvl 4 Akuma!