I meant to add, that if the male is barely big enough to eat fuzzies, he's likely not sexually mature enough to successfully breed, which is likely why you got slugs, even though they have been cohabbed the whole time.
(Which is dangerous with their size difference, and he's that little, he could become a meal to her.)
Corns can move up to adult mice about 170grams, and even then they have 130 grams at least to go before being at a good weight to breed.
Your female might almost be ready to move up to weanlings, so she has a ways to go before she's ready.
My recommendation: take the next year or two to research care and breeding, and then when you have time under your belt, in a couple years, when they are ready, then try your hand at breeding.
I know it's exciting to want to breed, but you have to take all factors into account.
Do you have the room to house all of the babies if you cannot sell them? Do you ahve the ability to feed all of them?
In all reality, you would likely get all normal babies, being het for Amel (if that is what you have), and not many people are looking for that.
You will see a lot of fancy morphs out there, and most people are looking for something in particular, not normals, even with common hets like Amel.
If you're serious about breeding, I certainly won't discourage you, we all start somewhere, but my advice is do not jump into it without having knowledge under your belt, and have a plan.
Figure out what your end goal is, what morphs you want to produce, and then invest in animals that will produce that.
Be prepared to house all of the babies. Have the proper size/amount of rodents necessary for the babies to eat. Have more housing for those that do not sell, as they grow bigger.
Start networking to create future customers.
Read all of the articles you can find on care and breeding, including what problems can arise in breeding (like being egg bound), and know what to do in the event that something unplanned happens.
In time, you will understand why we tell you these things, and in time, you will be giving advise to new people.
