I think there are Japanese names that would sound a bit better with
Rowan and
Lily (I have no probs with using names from other countries, so that in itself isn't an issue for me, despite the British LN)
Rowan Kagero is ok,
Lily Rumiko could use improvement imo.
What about:
Rowan KenshinRowan KentaRowan Taro (I like this best)
Rowan Ken
Lily AyameLily ManamiLily MarikoLily MioLily MomokoLily NoaLily RenLily Sayuri (Means small
Lily in Japanese)
Lily SoraLily Suzume