Japanese film Confessions

(1) Moriguchi found the bomb and moved it to Xiuzai's mother's studio. Xiuzai detonated the bomb without knowing it. (2) Personally, Moriguchi definitely wanted to get back at them at first, such as taking blood. If her husband hadn't found out and switched, it is estimated that Xiuzai and Naoki would get AIDS. Later, Victor, the transferred teacher, wanted Moriguchi to go home and find Naoki. (3) Naoki killed his mother, but the ending didn't say (4) Xiuzai killed his mother, and Moriguchi made a phone call. Both cases should be exposed. PS: Because Moriguchi's phone call revealed the final ending, it's hard to know whether Moriguchi's words are true or not, but I think Moriguchi should have finished her revenge, and the ending she said should be true.