The White Cat's Revenge as Plotted from the Dragon King's Lap: Volume 1

Nineteen-year-old Ruri Morikawa gets wrangled into a messy situation when her selfish childhood friend strands her in another world! To make matters somehow worse, a mysterious conspiracy then gets her abandoned in a perilous forest. Through an unexpected turn of events, she comes into possession of a mystical bracelet that allows her to transform into a white cat. Now that she's in the Land of the Dragon King, she has to hide the fact that she's human—which means spending her days as a little white cat, for the time being... But how will she exact her much-earned revenge against those who’ve wronged her while stuck in the form of a small, fluffy, cuddly kitty cat?!

[From J-Novel Club]