>start quest
>give potion to either a girl or guy
>return and talk to him
>find his lab and talk to him again, get a summon for free
>talking doesn't advance the quest anymore
>reload the area, talk to him, nothing changes
>reload the area again, now he decides to let the quest continue
>if at any point you proceed with ranni's quest he fucking dies for no reason
>if you do decide to follow his quest through to completion and give the potion to ranni, you don't get a new reward out of it, other characters disappear locking their quests unless you absolve yourself, and he still fucking dies