It was actually a mace goblin of sorts. I just panicked and never thought to organize a party or another squad of random dwarves to fight it..
You could have probably mobbed it with your 30 Dwarves and not lost a single life. A dozen or so permanently crippled, but eh. Victory is victory!
Kinda curious, how would you 'execute' the crazies within a fortress?
Incineration
Maceration
Crushing
Freezing
Drowning
Suffocation
Bleeding
Head shot
Decapitation
Spiky things
Spinny things
Goblin things
Animal things
Thing things
THE thing
Other Dwarves
Self inflicted insanity
Starvation
Dehydration
Exposure
Burial
Dwarven healthcare
Dwarven childcare
Becoming the mayor
Obsidianisation
Gravity
Gravity exploding
Unfortunately timed accidental fatal occurrences
Deadly dust
Deadly shower
Waterfall suicide
Waterfall regicide
Behavioural sink
Literal sink
FPS sink
Bone breaker
Infection
Poke poke
Smashyhammers
Old age
Cloud of mysterious solid liquid plasma
And however many more ways you can think of. Eye melting is a good one.
And what's the deal with vampires?
They will cut your normal Dwarves up. It's even worse because they used to be Dwarves themselves. If you are a heretic heathen you can harvest their blood to create a well of unlife and turn your entire Fortress into Vampire Fortress.
Why does food/booze in bedrooms relate to them?
Food and booze stockpiles gather lots of Dwarves. Stockpiles gather lots of vermin. Vermin gather lots of cats. Cats gather lots of Dwarves. Dwarves gather lots of Fun. This Fun can sometimes take the form of vampires.
It stands to reason that putting stockpiles in bedrooms and turning your Fort into Stockpile Fortress is the only logical solution to keep your Dwarves truly safe when everyone's dying.