[SPOILER] Path to Heaven_ harem?

So, I found out the names of his harem members, and I read the raws until the first one in his harem joined him?

I wanted to know how the other harem members meet him? (which chapter?) And what circumstances lead them to join him?

+++ does this novel do the typical thing (like almost all other novels) and forget a female lead after meeting/joining the next one? Leave one of them for a 100 ch? Maybe one of them is just forgotten until the end? OR they are all important to him and join him in his journey?