Just as the Sagittarius male is always a GUY, your Saggo girlfriend is always a chick. She is sporty, likes to yell risque stories or gossip at high-decibel and is most easily moved by discussion of politics, particularly the separation of Church & State and/or constitutions, the Magna Carta etc.
She usually has brilliant legs.
Your Saggo girlfriend is too restless to be still long enough to get facials, mani-pedis etc very often and secretly looks down upon those who do. She will cheerfully trek over the Himalayas or to Machu Picchu yet she finds malls, shopping and housework/chores horribly enervating.
She doesn’t have much time for complicated relationship crap nor needy and emotional clingy types. She’s streamlined it all into one approach and it works wonders.