Well, depending on how much your girlfriend snake actually psychologically resembles a snake, I'd say that it could very well.
However, a little problem here is that I don't actually know all that much about raccoons. I know that they're scavengers, and stuff, but not really much about their common personalities and mindsets, but you do, so I figure I'll just tell you something I've found about snakes, and you can figure it out for yourself.
Soo, snakes, besides potentially being venomous, are actually very vurnable in nature. They don't have any arms/appendages to defend themselves with, and they're not particulairly fast either. Once an oponent is within attack range with the snake, all he has to do is avoid the fangs, and being crushed and the assailent will be good to go.
As a result, snakes are generally pretty shy and reserved, and likely won't have much critique towards any potential mate that approaches them.
But, being reptiles, they love warmth! Both emotional, and actual physical warmth. So, I couldn't see why a snake wouldn't physically be attracted to a fluffy creature, such as a raccoon.
The emotional warmth is another thing, though.
Snakes have a tendency to stick with the partner whom they consider the most emotionally warming towards them. And, if a more warm PM approaches them, and shows interest, she'll likely have no problem in just choosing the warmest of the two.
This means that if your male character is somewhat rough in behaviour, he may risk loosing his snake GF to a warmer guy.
About the question of her coilling around your raccoon.
Yes, Rudy deffinetly has good reason to be concerned about Sarah intentionally coilling around him, to harm him. But, not accidently. Snakes have very slow metabolisms, and will avoid expending energy when they don't need to.
In the wild, a snake will eat once a week or two, and spend the rest of it sleeping, and louzily loitering around.
So, you won't have to worry about Sarah accidently crushing Rudy, as that would cost too much effort for it to happen without her actually intending to harm him.
Any more questions? c: