TAKOBOTO

when it comes to~ (neg. sense)
Speaking of my son, he really isn't very good at sports

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うちのむすこときたら、ぜんぜんべんきょうしないで、ゲームばっかりしてるのよ。

Speaking of my son, he is always playing games without studying.

わたしときたら、りょうりはまったくだめなのよ。

I really can't cook at all.

This is like [toittara], but only used in a negative, often self-deprecating sense.

jmadsen

Since this is always negative, one should only use it when talking their in-group members.

claytonian