Sailor Pluto does not know anything about 'Gallifrey', or 'Time Lords', nor does she have anything to do with alien invasions. (Well, not that sort of alien. She is not interested in certain people's mechanistic fantasies.)
"Look, I don't see why we can't get along –"
However, she is aware that if the other Senshi – the Outer Senshi in particular – come in contact with a certain person, she's going to have a whole kettle of fish to deal with. It would just start with "so why can't we go back in time to stop the Dark Kingdom?" and go on from there, with a side order of "yes, but I don't see why we can't go back in time five minutes and sort out that thing which we just messed up this time round".
"I only want to be helpful –"
The logical solution is to make sure that a certain person's blue box never comes anywhere near her area of time and space.
With extreme prejudice.
"No, really, Setsuna, can we talk about this –"
And, if necessary, with a Time Staff to the back of the head, though a violent energy discharge into his blue box also does the job quite nicely.
". . ."
There. Problem sorted out, and note taped to his console suggesting that if she sees him again in this vicinity then he is going to learn exactly why she has high heels.
"I honestly don't know why she's quite so upset about things, Pond. I was only a few hours late that time –"
The Guardian of Space and Time remembers everything. Including certain people standing them up after inviting them out for dinner.