Murder-suicide is a type of very sad and dangerous situation when one person decides to harm or kill another person and then themselves. It's like someone playing a really dangerous game where they try to win by hurting themselves and others, but in the end, nobody wins.
Sometimes, the person who does the murder-suicide is very upset or angry, and they feel like they can't cope with what's going on around them. They may even feel like they want to die, so they decide to take other people with them. This is really not a good way to solve problems, and it's not something that people should do.
It's important to know that if you or someone you know is feeling really upset or angry, there are better ways to cope than hurting yourself or others. You can reach out for help from friends, family, or professionals to help figure out what's going on and find ways to feel better without hurting anyone else.