Herman friendship cake

Today i have been given a Herman friendship cake mix by my good friend Gilleon. She has informed me that he has been nurtured to Day 4 and gave me a sheet of instructions o follow...
Herman is a sourdough cake, whose recipe dates back centuries. Similar to a chain letter he gets passed round circles of friends and families but actually isn’t as annoying. You must nurture Herman for 10 days before baking as a yummy cake. 

Here is a picture of Herman the on the day he arrived. he yeast in the mixture means he bubbles away constantly. The instructions tell me to cover him loosely and leave him on my worktop. Some days i need to feed Herman with a cup of each ingredient - milk, sugar and plain flour. On day 9 i split him into 4, bake one part, give 2 parts away, then use 1 part to grow him again. The instructions state ‘You cannot put me in the fridge or I will die. If I stop bubbling, I am dead.’  This made me slightly nervous...My kitchen has a very strong whiff of yeast now Herman has arrived.