Hi, the question is in the title. I'm asking it because I got a Soul Lantern after gathering all recepies. I used it to capture a blue slime girl. But now in other fights, Soul Lantern doesn't even appear in the item list. What do I have to do to use it back during other fights. 

Thank you!

When you release the captured monstergirl at theright farm or monsterhall, the soul lantern becomes empty and can be used again. You can also craft multiple soul lanterns, so that you don't have to run back after every single monster. :D