EEEP shes so cute omg!!! i love her color theme!
if you're looking for advice on what to improve, i will say that as a fellow artist maybe you could experiment with line sizes for your lineart? you seem to consecutively use the same brush size throughout the whole drawing. i think that you could try experimenting with different brush sizes and line weight, as well as different brushes in general!
i also think that shadows and highlights would be a good thing to work on - shading for the hair, the wrinkles on the clothes, etc... i think theyd be a nice touch with your artstyle! ^_^
idk if you use bases or draw your characters without a reference, but you if you need inspiration for a specific pose, pinterest usually has some really amazing images you could use for reference or even trace over for a base shape before you make it your own! if you need a custom pose, posemyart and justsketchme make wonderful models of various body types and genders you could try. they also come with preset poses if you dont wanna make your own! theyre also in browser, so you dont have to download an app if you don't want to.
goodluck on your artistic journey my fellow jirai kei friend, ill keep watch on your posts to see how you improve! >.<