Can a woman stay the night with a male friend?
I recently had to vacate my house, and I'm looking for a place to stay. A male friend of mine offered to let me stay a few nights in the spare room of his house. He is what I consider to be my best friend and we were never romantically involved. We are both single and we have both been clear with each other on our feelings (or lack thereof, romantically speaking). Is there a sin here even though there is no risk of scandal or temptation? We wouldn't even be sleeping on the same levels of the house, much less in neighboring rooms.
I'm not certain that you fully understand the concept of scandal. In common parlance, "scandal" is "a disgraceful or discreditable action, circumstance, etc." (source). But in Catholic teaching:
Scandal is an attitude or behavior which leads another to do evil. The person who gives scandal becomes his neighbor's tempter. He damages virtue and integrity; he may even draw his brother into spiritual death. Scandal is a grave offense if by deed or omission another is deliberately led into a grave offense (CCC 2284).
What this means is that your choice to spend several nights at the home of a male friend might not cause the neighbors to shake their heads and gossip, but it may cause your friends or other vulnerable souls to think what you are doing is okay. And so they may decide to bunk with a friend of the opposite sex for a reason they think justifiable.... And they may fall into a temptation against chastity because they did so.... And so on.
Unless your only other option is sleeping on the street -- and there are many possibilities short of that, such as staying with a female friend, or staying with relatives, or staying in a hotel, or even staying at a local YWCA -- then you should not spend the night in the home of a single man. Period.