Why not tell her sister? She needs to know about situations like this. Also, it could have been a house phone.

Ever heard of a landline? :) edit: sorry didnt see the reaction above when i posted this

1 Lets see your girlfriend do this and see how you react..

I definitely agree with you on not picking up the someone else's phone, respect privacy.

It's called common courtesy. Something that seems lost, nowadays. Also, as #9 said, it may be a household phone shared by multiple people. OP doesn't say that this was a cell phone.

16 It said "while she was out" that phrase makes me think it was a landline.. So try again..

Yup, the chances are they live together and it was a landline otherwise the OP would have deserved it.

If it was a landline, why would he want to have phne sex on a landline? There can be more than one phone, so if someone else were to have picked it up...

Where is everyone getting the idea that its her sisters phone?-.-

I definitely didn't notice that it wasn't a cell phone. Thanks guys! Also, the sister should know what happened, but her boyfriend should be the one to tell her. If it were me, I wouldn't believe something like that coming from my sister, but I would believe it if my boyfriend owned up to it.

9, it could be a very bad joke, for example.

44 Sad thing is.. Almost no boyfriend will admit to it unless confronted.. Even then sometimes no..

My cordless has a privacy function that locks out all the other extensions. I think its a pretty standard these days.

If hes dumb enough to try and have phone sex with the sister, hes probably dumb enough to do it on the family landline phone.

It could be a landline or she could've left her phone at home and when he called multiple times OP answered to tell him. I'd do something like that.

maybe it was a landline, people use those

He must have a raging phoner.

congradulations! your wildsweetchild has just evoled into feared!

#34 I don't consider it as a bad thing ;)

I really want to believe you're right, but since OP posted this here, I'm not so sure about that.

Eh maybe. Maybe her boyfriend has one of those strange senses of humor that you can never tell if he's messing around or not.

"Boys will be boys" ended as an excuse whenever he finished grade school.

Was it a girl or boy who answered the phone?

I agree. If he would say that to the sister who knows what else the guy has been up to.

#6. Good idea! Maybe she'll take the hint and plan a threesome!

Imagine if the mom had picked up instead. I wonder how that conversation would have went.

... but FYL indeed. No one should ever have to be in that situation.

How about just using your hand, and not involving outside partners when you're supposed to be in a committed relationship.

While I agree with you, there's no indication that they were in a committed relationship, although that's the general assumption. Still, the boyfriend shouldn't have involved someone who's unwilling.

Yeah, but if the boyfriend is going to engage in phone sex, you don't hit on your girlfriend's sister. That's what paid sex talk lines are for!

Parts is parts (Old Wendy's commercial)

Well we know they sound alike.