Train Survival: My Synthesis System Is a Little Off

The protagonist relies on 3 F's to combine into an S. The transsexual succubus has props! In the early stage, every E is a good thing, but there is almost no D! In other words, the protagonist will use this equipment for a long time! Then if there is one there are two! Sooner or later there will be the second Dark Summoner! 🤮