I actually overlook the fact that he had no soul while doing it, because Spike even without a soul loved Buffy. And that's the thing. The souless Spike loved Buffy, so the souless Spike shouldn't have done that and would never have done that on a regular day. It's just not him, doesn't matter soul or no soul. He didn't drop by to have sex with Buffy, and obviously didn't come there to rape her either. He came to appologzie, to show Buffy that he still loves her and cares for her. He didn't have any cruel intentions (I don't mean SMG's film!), he never wanted bad things for Buffy. It's not a defense of Spike here by saying he had no soul, I just defend the fact that it wasn't him there. The real Spike, the regular Spike would never hurt Buffy. It was mostly an accident. Like with a car accident-it's bad, it hurts people, but it's not on purpose. I don't see a reason to blame anyone on the AR, simply because it wasn't intentional, it wasn't what he wanted. And like a car accident, sometimes things (car) loses control. It's sort of the driver's fault, but not really. It's not like the driver left his house, started the car, and decided he will pound on the car infront of him.
Now, if that was Spike's intentions, to come there and MAKE BUFFY have sex with him no matter what and then rape her when seeing her crying her eyes out and thinking to himself something like "yeah! You deserve it, bitch!"... then I couldn't stand seeing Spike's face anymore. But clearly it wasn't the case.
I'm not saying anything that justifies what happened to Buffy by Spike. And again, I don't defend him for doing that. I simply say that there was no intention there in hurting Buffy, that wasn't his goal, and he wouldn't wanna do that if would've noticed how much it hurts Buffy. Spike loves Buffy to death. He wouldn't have done anything that would hurt her, so that proves that it's not s simple case of girl raping. Spike's not a rapist (in his heart I mean, it's just not him!). That's why he freaked once realizing what he's done.