Is the black panther and tiger together? Or got their own story ?

Story and he's just a cat not a panther same author

*ahem* I think you got it mixed up... 'cause I'm pretty sure he/she meant Kagetora (tiger) and Kuroe (black panther) not Kakami (leopard) and Shingo (black cat).

Soooo, to get back on track:
Dunno IF they have their own story planned or already out. But it's possible.