I'm not sure specifically as I haven't read this particular fanfiction. It could potentially be about Ratchet and an original character (oc) being put in a cage during lockdown, perhaps exploring themes of confinement, their relationship, or how they deal with this unexpected situation.
One common theme is empowerment. Writers often depict the female Ratchet as a strong, capable character who can take on any challenge in the universe. She might be shown to be even more resourceful than her male counterpart in some stories.
The sense of isolation. When you're locked down, you're cut off from the outside world. So, if something scary happens, there's no easy escape or immediate help. For example, if you hear strange noises in your house during normal times, you can just leave. But during lockdown, you're trapped.
Another option is to join Ratchet and Clank fan forums or groups. People there often share and discuss their favorite fanfictions. They might be able to point you directly to some great stories with a female Ratchet. For example, Reddit has some active Ratchet and Clank communities where fans exchange such information.
There were also stories of people losing their jobs suddenly. For instance, a restaurant worker. Lockdown meant the restaurant had to close. He had no income and faced difficulties paying rent and buying food. It was really tough for him and his family. He had to rely on the little savings he had which quickly depleted.
One scary lockdown story was when a family heard strange noises at night. They thought it was just the wind at first, but then they saw shadows moving outside their windows. They were really frightened and didn't know what to do. Another was about a person who got stuck in an elevator during lockdown. It took hours for help to arrive as there were so few people around.