I'd stop him before he could do that. I don't care if the cliff magically appears the 秒 he shows up and I only have that fraction of a 秒 left to stop him. I absolutely will stop him before he can even think about jumping. I don't care if I have to drag him away によって his ears または knock him out to prevent him from jumping, he absolutely willnot jump off that cliff.
And if によって some slim chance he managed to, and that is a very slim chance, then によって george, I am jumping off right after him. Yeah, I'd die. But after seeing him do something like that, I wouldn't even have the will to live. If we couldn't share our lives together while there was a chance, then we will at least share eternity's slumber together.
Edit: ... OH WAIT! WAIT! BLIND'S ANSWER REMINDED ME! KID HAS BEELZEBUB THE FLYING SKATEBOARD!!! THERE IS HOPE FOR US YET, MY LOVE!~
@Blind Yeah... heh heh.... XD I kinda sort of got caught up in the emotional, painful, terrible thing I envisioned and I kinda forgot all about Beelzebub... X'D I'm stupid...
If it's the character I have in mind. I would jump off with her. Considering she has a ほうき and can fly. And knowing Marisa she would do that for thrills.
If Peeta Mellark came alive and jumped off a cliff, I would literally go batshit crazy. Jumping and screaming and crying and groaning and beating the ground with my fists and breaking all sorts of crap. Then I would become depressed and become a schizophrenic and a psycho.
Jump on his back and jump off the cliff with him. Then he'll do that "windy thing" were we fly around and just pull pranks on everybody. If not, just watch really "bad" movies. So anything with Nic Cage in it.
Follow him so we could die together. Then realize as I'm falling he is perfectly safe, laughing his 尻, お尻 off at my stupid action. ;n; Izaya is such a troll. But I 愛 him.