Someone how can make room light up, by walking in the room.
Someone to love.
Well stated, sir. You win one free internets.
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You know, most of the other answers here on this thread focus on appearance rather than other things. The OP said "companion" which I think would imply a more long-term arrangement. If you are married (or some such long-term relationship), other stuff is needed to keep you two together: if you can't stand someone's little habits or other aspects of their personality, or if they are an axe murderer or some such, then it does not matter how hot they are.
While I will discuss appearance here and there in the following rambling answer, I'll also go over aspects of my ideal companion that deal with personality ...
Female, duh. yeah, I know, obvious, but sometimes the obvious needs to be said.
Given two women of identical appearance, I would be more attracted to the one that knows how to set up a cron job in unix/linux then the one that doesn't.
Hmm, thinking about the above, I'd say i'd also be attracted to a woman who knows anything technical or scientific.
She'd be strong willed. No pushover, this one. But not stubborn for its own sake: not the sort to argue for its own sake.
Honorable, trustworthy. In Morrowind terms, Redoran ... sort of.
Confident. Assertive but not obnoxious or agressive for its own sake.
Outgoing, though not annoyingly so, she'd be the sort to pursue me rather than wait demurely for me to work myself up to stammering out some lame small talk!
Someone who is as
cheapthrifty as I am.
No smoking!
Butch (dress, hairstyle, mannerisms, aspects of personality as well) and nerdy and cute. Yeah, I know, it's kind of pointless for a guy to like butch women (because it seems they tend to be into other women rather than men?) but we don't choose what we are attracted to, do we?
Someone who is a people person. This would make up for my own lack of "people skills". :/ (does this conflict with nerdy? discuss?
)
Into PC gaming (but not MMORPGs, sweet Azura ... no no no).
Music? I'd like to say I'm open minded and don't care what she listens to ... but that would be a lie.
We'd have to agree on music. Like me, she'd be into various electronic music, from new wave & disco through to industrial, trip hop, house & techno and the various bits in between. Some bits of punk & metal & rock & hop-hop in there as well.
Sane. (weird & cool, but sane).
Smart.
Better at "thinking fast" or thinking under pressure then I am.
Weight: hard to say. I'd say "normal" or "average" but these definitions change over time and vary with location/culture. So I'll say: heavier than anorexic, lighter than zaftig.
I'm certainly not turned off by muscles. Mmmmmm, a hard woman is good to find.
But am undecided if this is an "ideal" requirement or not.
Tall is fine ... fine ...
FINE but not required. Given that I'm short, many woman are going to seem tall to me anyway.
As for the erm, chest, too big is as bad as too little. No balloon-like fake boobs.
Really light skin used to be my favorate but I've seen enough hot women of every color that I no longer have a preference (well, aside from the fact that I am not attracted to freckles).
Black "raven" hair (Though I have, on rare occasion, felt attraction for some woman with other hair colors), straight, cut really short. Short hair is totally hot.
Dark brown eyes.
Thick eyebrows. I liked them when even they were out of fashion (like the early 1990s, shudder, a bad bad time for style and fashion).
No makeup. People keep saying that a woman who looks good without makeup is a fantasy ... but I've met several, so I'm sticking to my guns on this one.
I like a low, smooth voice. Not a "chirpy" high voice
Something along the lines of the Dunmer women in Morrowind/Oblivion (mmmmm, like Cutter, or the boatwoman in Vivec who says "where would you like to go"), or Grace Jones back in the day.
Picky? Well, the OP did say "ideal"!
p.s. I am heartened to see the amount of other posters saying black hair as part of their ideal. It is so nice to see I'm not the only one who prefers it.