Is that income? Alternative pension equalization payment

I'm asking for a friend who doesn't have Reddit: She's divorcing a foreigner who isn't in the German pension system. You do, but you don't know your way around here. There is therefore no normal pension point sharing pension equalization. They therefore entered into a private agreement. He pays her a monthly amount for 5 years, which she is supposed to invest in her own precautions. Does this amount have to be taxed? Does this count as income? What kind of product/system would be there?