"Твоя кошка пьёт из моей чашки."

Translation: Your cat drinks from my cup.

[Neon_Iceberg]

You don't know the whole truth dude, actually you drink from its cup )

[GIvanovJG]

I that case, an appology towards the cat is in order.

[Akuhime-sama]

I let my cats stick their noses in my water bottles. It's very cute.

[SweetDog_37]

In what form is чашки here? I am having difficulty understanding the conjugation in this case.

[Neon_Iceberg]

Singular, in genitive case:

http://bezbukv.ru/inflect/чашка

[beni945534]

Why моей чашка and not мой чашка?

[MichaelJoh56245]

I believe it's the locative words.
--моя чашка = my cup
--в моей чашке = in my cup
--в мою чашку = into my cup
--из моей чашки = from my cup
--к моей чашке = to my cup

[JWolf88]

I put "Your cat is drinking from my cup" Should this be accepted?

[Neon_Iceberg]

Yes, your choice is correct. Click on the "report button" if this one wasn't accepted.