"If I need to know specifics"? LOL My dear misguided one, this is a LEGAL forum where details are paramount. The accuracy of your question is directly related to the accuracy of your answer. You are going to scold me when YOU aren't even equipped with enough forsight to have paperwork signed BEFORE offering money to a room mate you think so little of that you would be willing to "ruin her" if given the opportunity? Aren't you just a model citizen!!

You come into a forum such as this, asking people to assist you when you have done stupid things--you provide NO details , offer ambiguous statements that mean nothing, then expect a solution to your own stupidity and poor judgment.

If you don't want people to presume, fill in the blanks yourself and ask the question in a cohesive manner. You never mentioned she was your landlord--you called her your room mate---how does your room mate have the authority to reduce your rent? Is she simply paying it to your landlord herself, or is she the landlord? And, if she is giving you a hundred dollars OFF your rent in lieu of payment, that agreement supercedes your original agreement to pay. Reread until you understand. You accepted the terms of the second agreement, so the first verbal contract is invalid regarding the terms of repayment. Understand? A hundred dollars is a hundred dollars---unless she purposefully raised the rent--there are dozens of possibilities that could be the correct answer to your question but since you haven't even mentioned the state in which you reside. Each time you post, you offer more unclear details that result in even more speculation.

Realize that your accepting the verbal agreement to receive a reduction in rent SUPERCEDED ( takes precedence over, renders the previous agreement invalid) the verbal agreement you had for her to repay you in cash, making the second agreement the one that the court will uphold. So, as you can see, your "new" details you slathered on in a jumbled mess changes the legal answer to your query. This means you cannot, as a matter of law, expect her to sign something upholding the original agreement since you both agreed to change the terms ( reduction in rent ). Understand?

As far as "ruining her"? Well, again, that speaks to you character and your lack of regard for friendship as well as your inherent bent to be prejudicial and unfair. Also, you decline to explain the term "ruin her", so I can only assume, but be advised that malicious behavior, such as harassment, slander, or libel IS actionable under the law--and it may be YOU who is the one paying and not her.

Don't like assumptions? Be clear.

Or solve your problem yourself. * shrug *