The Bloodfang is located in the fields of a farmer in the city of Britain in Ultima VII. The farmer reports that the "tiger-lion" got out of the vessel, and told him to "Kill Rathi," before accidentally getting impaled on the farmer's Hoe of Doom (or something like that - and the hoe really exists). Unfortunately, the farmer does not know who Rathi is, or why Rathi needed to be killed. After the tiger-lion died, the farmer cooked and ate it.
Ultima Underworld 2 has a race of four legged (i.e. non-bipedal) felines that are used as either guard animals or beasts of burden (I don't recall which). Although they pretend to be dumb, they can actually talk, and speak to your character when given the opportunity. They have legends of when their ancestors used to travel between the stars, and iirc, their name is an anagram for Kilrathi (or very similar to it - its been a long time since I played that game).
There was also an April Fool's gag that Ultima On-line ran a while back that involved news stories of Kilrathi ships attacking the city of Britain. It appeared on the official UO site in the news section.