Well, I guess it's my turn again.

I try to heal myself!
heal roll: 4
SPImod: 9
I healed myself to full health (15/15)

Backstabs tries to attack the white mage!
Hit roll: 10
Enemy's dodge roll: 1
mini-crit!
12 (max weapon damage x2) + 6 (Agimod) - 4 (enemy's defense) = 14 damage.
...that white mage had 5hp left, so... I think he's down and out, don't you?

The ranger attacks me!
My dodge roll: 3...
Enemy's hit roll: 14.
It's a hit, obviously.

Damage roll: 3
3 + 9 (Agimod) = 12 - 6 = 6 damage.