Fetching details from the dictionary...
to be deep in talk
友人と話し込んだら、あっという間に3時間経っていた。
My friend and I got so deep in talk that three hours passed in the blink of an eye.
隣人と話し込み、子供を忘れてしまった。
I got absorbed in conversation with my neighbor and ended up forgetting about my child.
彼は話し込む癖がある。
He has a habit of getting deep in conversation.