Particle
speaking of
Colloquialindicates emotional closeness or annoyance with someone
あっ、赤くなった。陸くんてば可愛いっ!!ふふふっ。Ah-you've gone all red. Riku - that's so cute!! Ha-haha. (I told you) already; come on
Colloquialindicates annoyance (in sentence-final position)
Also written ってば