So, like the title says, I am seeing one girl (Girl A), and just last night something that has been building between myself and another girl came a head (Girl B, k-close). So, I want to see both of these girls (call it non-exclusive dating, mltr, harem, what-have-you). But, the problem is that my roommate/land lord (female) is good friends with Girl B, and knows about Girl A (she also helped me get introduced to her, friend of a friend). She told me that if I wanted to pursue Girl B, that I had to break things off with Girl A. I know that this is just an emotional response, because she doesn't want her friend to get hurt, but I also understand that it isn't her call to make. I still need to have the conversation with Girl A about me not wanting to date just one person, and I also need to see if I enjoy being with Girl B (we don't have much one-on-one time). If I am, I know I need to have the same talk with Girl B. I guess my problem/question is, how do I tell my roommate that we're all adults, and that she needs to let us figure it out, without turning it into a shouting match? Also, what is the best way to bring up the not dating exclusive topic (I know that I must accept the possibility that she will end it, and I have)?

Note: Girl A and Girl B are not in the same social circle, so that is not an issue.

though one,

i think you should tell your land lord that you are not sure which one you want to date because you don't know enough about girl b and want to know her/both girls beter before you make that choise.
i can't give you any advice on dating them both SPAM
but if you want to date more people at the same time you'd have to brake up with girl b otherwise the landlord will keep interfering

good luck man

_________________
don't take life to serious and enjoy what's comming to you,
you're never alone, love those who deserve to be,
and at last never judge and be your own unique self

Well, I got one of the balls back in the air. I had a talk about not being exclusive with Girl A, and she agreed, and was looking for the same thing. It was not the smoothest conversation, because she thought I was trying to politely brush her off. This was because we hadn't gotten beyond a certain point physically, so she misread that as disinterest. The reason I didnt take it further was because I didnt want her to think I was using her, but I guess that is a limiting belief. That was my fault, and I will learn from it, and not make the same mistake with Girl B.

My transition to the non-exclusive topic was roughly as follows:
I have enjoyed getting to know you, but I feel like I have to be honest with you. I am not looking for a serious relationship right now, or even something exclusive.

The conversation progressed from there successfully, but I do not think this is an effective way of broaching the subject, and dont recommend it for other people. Does anyone have a good transition for this?

Follow up: Are there any females on here who can confirm/disprove the idea that if you go beyond a certain point physically, and then drop the non-exclusive idea on her that she will feel used?

(Insert 2 girls 1 cup joke here)
Females? Better to ask a PUA.

It all depends on the level of emotional investment involved. Before you let her invest any significant amount of emotion into the whole thing, you need to manage expectations, which may be exactly what you have done.