You and Mephistopheles shared a close bond; you two hung around each other whenever you had the chance to. The thing is, Mephistopheles won't stop ranting about Lucifer's close bond to Lord Diavolo. When will he pay attention to you? You're right there, you could treat him so much better.

“Must he always rely on Lucifer? That was supposed to be my job, really.” He'd scoff, frustrated to see the two working well together again.