It is an odd situation we put ourselves in when sitting. You are living in the personal space of a stranger. If you have crossover then you have interaction in person. We have been on sits where there is tension between the hosts or there is a family situation they are worried about before they go away. It is a strange dynamic. We have had hosts that I have thought maybe we could be friends as we seemed to click well, but mostly that’s not particularly practical. Just musing on the vagaries of sitting I guess and may or not be helpful 
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@Itchyfeet I had to google it 
I could have googled it but have hopefully made a point that not everyone gets these abbreviations
I had a hunch that was your point @Smiley
Smiley, I had no idea what TMI stood for either. Wish people would write in full instead of assuming everybody knows wwat TMI stands for? If as I saw below it was just, too much information I cannot see a problem. Many homeowners do add other information regarding their trip away, along with info regarding pets etc. I even had the wife of a couple sending me a text at least weekly for a couple of months leading up to the sit. Frequently people do come across as friends and send friendly messages.
If not wishing to become involved in small talk I think I would just reply with something like, sounds ,like you are having a great time, and then go on to only mention about the pets in the normal daily update. Doesn’t seem a need to make a song and dance about it.
You mean she made sexual remarks via text?
That is super inappropriate, I would tell her off for it, and for it not to repeat again. If she had a problem with it I would cancel the sit right away inform THS that you didn’t feel safe and wanted to leave right away.
the just apply to other sits in the area and fingers crossed find something new.
No point putting yourself in an uncomfortable situation for accommodation. Stay safe
Also, what did she say? not because I am snooping, but I just looked up overly familiar message on google to confirm what you mean by that, but it seems so extremely vague on google that so many things could be considered overly familiar messages.
Was she just saying she would like to travel with you from a jealous perspective? as in “Wish I could travel around the world with you?”
For clarity, i edited the OP to remove some of the detail and add some additional anonymity.
I appreciate how it impacts the context of the convo. 
Hello @Mark_B
I understand that the message is edited, but now I feel it’s so vague that it’s left to everyone’s own interpretation of what it could mean.
I think the edit might be counterproductive to any constructive discussions.
One person’s “overly familiar” can be another’s friendly. So, she said something about wanting to travel around with you… And for this you tried to report her to THS? Or have I interpreted it wrongly?
I saw the original message, not sure what the big deal is as we are adults here. The HO was making reference to having desires for people (in more than a friend type way), could be towards Sitter or others on her vacay, or both – not quite clear. This is of course inappropriate convo to have with a sitter regardless of the level of comfort and friendliness of either Sitter or HO.
Sparing details. I don’t want to get involved, it’s probably one of the 3 strangest human relationship things I have heard about.
(Edited in line with the posting Guidelines)
Just tell her you aren’t comfortable with that kind of texting because you have a partner you’re uber obsessed with (even if you don’t) but you are happy to speak about the pets from here on in. Just be clear about your boundaries or just leave and book a new sit somewhere in the area (if possible). Next time, don’t agree to the sit/cancel if red flags 
are/become evident. We shouldn’t feel obligated to put up with sexual harassment.
A reply I posted to this - which suggested a rather gentler way of seeing the situation - has been removed. I have no idea why. If any mod has an idle moment to explain…
@GentleSitter how are things going now? Do you have the HO wrangled in on their message topics? Are things going smoothly otherwise?
@GentleSitter
A couple of weeks ago, I applied to sit in a location I am currently visiting during the summer and plan to leave at the end of August. The host replied that she had just offered the sit to someone else but would love to have me in October when she would be traveling to a “nice country.”
We exchanged a few messages and got quite friendly in the process, so I replied to her jokingly that I would rather go with her to the “nice country” than sit her pet at my current location in October. It was a 100% joke, and she took it as such.
Could it be that you are somewhat misreading the room and seeing things in black and white only?
l agree. I find very many of these comments as gaslighting the OP.
If HO were a man, I think the responses would be very different.
OP is not able to tell us in detail what this HO has said and done. Can’t we just take OP at their word?
Possibly it was yet another comment treating the OP like they’re “overreacting” and “taking things the wrong way” etc. The mods likely have full knowledge of the communications.
You have control of how and where things go. Finish the sit and press on. The pet owner will get the message.