Does Charm Person break if the charmed person's minions are attacked?

Question

I'm trying to clarify with my players what is the effect of charm person on a very particular situation:

1. Combat starts, player engage some zombies in battle and kill one of them via arrows.
2. Fighter goes into the room and discovers a Necromancer and some zombie minions under its control.
3. Druid wants to cast Charm Person spell on the Necromancer.

Assuming the necromancer fails the save, I'm having doubts about ruling how it will work.

According to answers to this question, charm person would only protect the druid, allies would still be attacked.

But the doubt here is about the part that says:

If it fails the saving throw, it is charmed by you until the spell ends or until you or your companions do anything harmful to it.

If anyone attacks the necromancer's zombies, would that be regarded as "doing something harmful to" the necromancer? Or would it not break the spell because the attack is directed at one of his minions and not the necromancer himself?

Additionally, since the Druid has already attacked one of the minions, would the charm spell even work?

Answer 1

To answer your last question first:

Can you charm somebody if you're in combat with their minions?

Sure, of course you can. The charm person spell doesn't say anything about being unable to us it in combat. What it says is

[The target] must make a Wisdom saving throw, and does so with advantage if you or your companions are fighting it.

Does fighting a guy's minions mean you're fighting him, granting him advantage on his save? Well, it's somewhat up to the DM, but yes, I think that's a very reasonable interpretation. You are clearly hostile and actively violent in the necromancer's general direction. The intent of the rule seems to be that charm is not very effective in a combat situation; for best results, you should be using it before combat breaks out, or when combat isn't really an option.

Does attacking a minion count as attacking the master and break a charm?

Again, this is going to be up to DM interpretation to some extent, but by the text of the spell, "it is charmed by you until [...] you or your companions do anything harmful to it." Attacking a minion is not direct harm to the creature, so it doesn't actually break the spell, though I'm sure he'll protest mightily.

From his magically-altered point of view, the necromancer's best friend (or his best friend's friends) is hurting his other friends (or breaking his stuff, depending on how he looks at his necromantic creations), which probably won't go over well, though it won't actually change his opinion of the caster.

Of course, a DM can make up rules on the fly. They might decide that under the circumstances, each time a zombie is destroyed, the necromancer gets another save against the charm spell.