So, here's the rundown of this post...
Backstabs tries to steal something from the ranger!
Backstabs' roll: 5
Enemy's roll: 13
FAIL!

The ranger tries to attack me!
Ranger's roll: 16
my roll: 18...
My luck: 10, so... 18+5... 23 total
Ranger's AGI: 17, so... 16+9... 25 total... HIT!
Damage roll (1d3): 1 + 9 (AGImod), 10
Defense: 6, so, the archer deals a total of 4 damage, leaving me at 9/15 HP (The ogre potion didn't heal HP, but did bring my max HP back to normal, hence, the extra damage.)

The white mage tried to heal the ranger!
No roll needed, auto-hit.
Healing roll: 2.
2 + SPImod = more than the damage on the ranger, so, ranger is once again at full health. (11/11)