If you miss the interest payment, Viet will probably bring some of his yakuza friends to your place.
Koichi has enough money in the bank to live on his interest.
I’m afraid there is no one here who can answer your question right now, but you can also check your interest rate online, if you can connect to the Internet.
You receive profit at every breath. What kind of profit is this? It's interest. As time goes by and as you take more breaths you gain more bank interest.
This is a jukugo word, which usually means on'yomi readings from the kanji. If you know the readings of your kanji you'll know how to read this as well.