InconnuTrackers
As you saw when you created your character, each character has trackers: Health, Willpower, and Humanity, plus Hunger and Blood Potency for vampires. Inconnu also tracks lifetime and unspent XP. You change these with /character adjust.
Its optional parameters cover nearly every aspect of your character.
Example: Nadea takes two Superficial Health damage, one Aggravated Health damage, and one Superficial Willpower damage.
/character adjust sup_hp:+2 agg_hp:+1 sup_wp:+1
Plus, minus, or nothing
In the example, +2 and +1 add damage, and - would remove it. Leave off the sign, and Inconnu sets the value instead: with three Superficial Health damage, sup_hp:2 brings it down to two.
Why not just subtract Health? The health parameter sets the size of your Health track. Damage is tracked separately, so you add damage rather than subtracting Health.