Dragonmaid Sheou vs Dark Magician The Dragon Knight

[LuigiJoseph]

The other day I was playing with my friend.

He summoned Dragonmaid Sheou and to bait him to get rid of her, I activated my eternal soul to bait him into negating it. Which he did negate it, and it does say to destroy it after negating. However, I had on the field Dark Magician the Dragon Knight which he protects my spell/traps from being targeted and destroyed by card effects.

However, for some reason it had been destroyed. Could anyone explain to me why?
I did all this to make sure my eternal soul stays on the field but it was destroyed. I find it unconvincing.

[Tunnel Sharks Rule!!!]

I'm guessing it's because it negates the activation of the card and destroys it so Dark Magician can't properly protect it yet

[LuigiJoseph]

It negates the eternal soul but Dark magician is not negated. So techincally, the eternal soul is negated yes, but the DMDK is still active and his effect should be applied

[HeraldOfOpera]

Negated activation means it was technically not on the field yet. Yes, this is weird. Welcome to Yugioh.

[LuigiJoseph]

Huh. Even it was already active on the field before ?

[Chaos 混沌 カオス]

DMTDK should protect even facedowns as well. Weird.

[LuigiJoseph]

exactly, that's why i was weirded out by it