If y'all didn't remember, in chapter 3 leo recalled that in the seabed there is a sage who fused himself with great tree. Im guessing in the last page that's the sage
Author forgot his world setting geez, for an advanced civilization that can made a floating city, they can create and send underwater drone to supervize what is it, instead they sending people to his death.
Good lord... The action choreography is a complete mess. It's as if the artist was trying to overcompensate for something. Plus, the progression and strategies of the fight are as bad as the gratuitous fan service. But of course, what else should we expect from another harem manga where the only way to make the MC look good is to have all other males be scumbags?