<human>: Give me the gist of the text in a nutshell

I am a college student and live in an apartment with two other girls. We are definitely all on friendly terms, although I kind of have my own life, and so don't hang out much with either of them. One of the girls has also consistently had problems with other people she has lived with because she is very intolerant of messiness and is also very conservative (read: very judgmental of previous housemates who she has heard having sex/showering together/etc). This weekend is a four-day weekend for us, as well as Valentine's Day weekend, and so my boyfriend (who lives in another part of the state) is coming to visit.
I have my own room, and am not a loud or messy person, nor is my boyfriend. We will have sex, but we are not loud, will not do it on communal furniture/in communal areas, and most likely will not do it unless she's out of the house, anyways (it's not a big apartment, and she's out a lot, to be fair). However, since she has shamelessly shit-talked former housemates who she has had trouble with, and I am a month into a six-month lease with her, I would like to preserve the peace. I'm a little worried that having my boyfriend around will make her uncomfortable, and would like to avoid the situation. However, I don't want to ask her permission for him to stay with me, since I am paying rent and he already made arrangements to come see me. 1) Should I inform her of the dates when my boyfriend is going to be here, ASAP, so she can prepare? 2) Since we don't hang out much, would it be too weird/awkward for me to offer to take her out for lunch/dinner/a cup of coffee as a thank-you for being tolerant of my boyfriend being in town for four days? 3) Is there anything else I should do to make as ABSOLUTELY CERTAIN as I can that I will be maintaining the peace?
Thank you so much!!!
<bot>: How can I have my boyfriend over for the weekend while maintaining a friendly and comfortable relationship with my uptight housemate?