I'm going to do whatever it takes to put an end to it.
There's no reason for you to endanger yourself. Doing your best to stay safe is help in of itself.
You're not going to accept no as an answer, are you?
Fine. I'll let you know if anything comes up.
I owe you my thanks as well. I'd almost forgotten what it felt like to really help someone.
Right. I'll be waiting for you to tell me how tomorrow goes.
Other options:
[text]
I'm going to do whatever it takes to put an end to it.
[text]
[text]
There's no reason for you to endanger yourself. Doing your best to stay safe is help in of itself.
[text]
[text]
You're not going to accept no as an answer, are you?
[text]
[text]
Fine. I'll let you know if anything comes up.
[text]
[text]
I owe you my thanks as well. I'd almost forgotten what it felt like to really help someone.
[text]
I'll talk to you again soon, Terui-san.
[text]
Right. I'll be waiting for you to tell me how tomorrow goes.