^ They're right, though I don't think Lunch is ever referred to with -tan. Not from what I've seen anyways. I've gone through and tagged all the images i could find of Lunch, as well as the other girl with her, who is named Potechi. I don't know the penguin's name (if it has one) but will update if I find out. For this doujinshi, there's another artist credited named "Fukunaga", but I don't know exactly who they are and I don't think anything in this image is their work anyways. I added a translation, my Japanese is very shoddy but I think it communicates all the information correctly.
Lunch's adventure begins, ni~!!
Lunch seems to have a speech quirk where she sometimes adds "ni~" (に~) to the end of her sentences.Popular "Moetan" illustrator POP draws nekomimi girls ·
Lunch's magical fantasy!!POP & FukunagaLunch Box