Spoiler:
With Matsuda. He basically was given a choice whether to live himself or save hundreds of other people instead. Being blown up by a bomb might be a fast death, but getting to the point where you give up your own life, watching the timer countdown to zero, knowing you have only 3 seconds to let others know the location of the other bomb and knowing your gonna die right after. Mentally it must be torture and not just for Matsuda either, also for everyone around him watching, but knowing that they can't lift a finger to help him.