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There is light novel, it's a novel. In Japanese these are different! And unfortunately, the one book is not translated. If you want, you can google translate the unedited/unimproved version that's the web novel. Just look up the japanese name and find a website titled syosetu. NOTE THOUGH, a good amount has changed in the publication ver.

There isn't a light novel* I meant.

Question. What is the difference between a light novel and novel? Is a light novel basically what we consider a novella (i.e. a story shorter than a novel, but longer than a short story)?

It's exactly as you said, but not necessarily "short" in terms of how many books there are. A light novel has less complicated characters, sentence structures and generally less pages. They can have multiple volumes, though.

Meanwhile a novel is the opposite and usually have less volumes. In this case, "She Likes Homos, Not Me" had a single book after its web novel was serialized.

Thank you for the clarification!