*Smirk* "Well... About time something happened."
I would then enter battle with it holding two katanas in what might be considered standard anime battle format.
First bout, my win, fail to land killing blow in time, Demon powers up, next round.
Second bout, Demon's win, Demon starts insulting me and threatening everyone I hold dear and such, I get angry & counter with friendship or honor or something, I power up, Final round.
Third bout, my win, I use some OMG move and completely destroy Demon.
Realistically, however, I would probably swear before running off or grabbing something to fight with and charge only to die in a minute.