It allows you to apply various types of liquids in a controlled manner. As I try to do with all of my LoRAs, it is aimed at having minimal effect on style and composition. You can use it with any weight, it depends on the amount of effect you want. In some cases you can even go up to 1.5 weight.
There is no specific trigger word so you can use your imagination, and you don't need to be bound by booru tags. Some of the words that help give most effect are: suggestive fluid, dripping. But if you use any NSFW tag it's likely to activate.
If you're not feeling imaginative, here's some ideas for prompts you can use:
sfw: ice cream, chocolate, honey, whipped cream, mustard, ketchup, mayo, water, shampoo, soap
nsfw: sex, fellatio, tentacles, etc.
nsfw liquid: cum, cum on hair, cum on face, cum on breasts, cum on ass, cum on stomach, cumdrip, cum string, cum pool, excessive cum, bukkake