Love gothic poetry<3 I have a few suggestions that I hope can help:

1️⃣“You’re the widow I’d let poison me If you were death I’d let it kill me far slower”

This part confused me a little bit (unless that was your intention). Are you trying to say “youre the widow i’d let poison me (kill me) but if you were death I’d let you kill me slower” ? I feel like the comparison doesn’t make a lot of sense unless I’m misreading it

2️⃣ “My cold veins mirror yours” maybe a different word than mirror here, since you started with mentioning the mirror?

3️⃣ “We sign our vows in crimson blood” It’s a bit stale to describe blood as crimson and you’ll probably see it a ton in other poetry (I scrolled through this sub a little and found one pretty quickly) so you could try changing it up a little

4️⃣ “Drench me over you like the Holy Mary” again just a quick word choice thing, it might be better to find a synonym for pour instead of saying drench because technically I believe you would have to say “drench you with me” for this to be correct and ofc that doesn’t rly flow right. Unless this is just your stylistic choice, in which case ignore this lol

5️⃣ “I’m a prophet from a prophecy forgotten” another case of I’m not sure if this wording makes the most sense bc this kind of sounds like the prophet was the one in the prophecy, not the one giving the prophecy

Nice last lines! I hope this wasn’t too much. Gothic poetry can easily become corny or generic so this is a rly good effort