[Q] What Messaging app is this?

I was scrolling through new themes on the Play Store and I came by Carbon UI for CM12, by Zyxxeil when I noticed something in the screen shots.

[IMG]Attachment 3515606[/IMG]

Does anyone have any idea what app this is? It's probably themed, but I still don't recognize it at all.

Sent from the Nexus6ix

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