Here what i found so far:
1) in the recollection room there's a 4th boss that you can fight. Winning it will grants u "kiss skill" (you need to equip it). With this skill you can start kissing all the girls + fairy + boy. Im not sure if you can trigger this event outside the recollection room. Losing the fight does not grant you extra scene.
2) There's a new event that you can do before you trigger the new destroyer event. Pretty straightforward, enter the manor. Talk to thief girl in 2nd floor. Come back to 1st floor and enter the first room for some event. Talk to thief girl and reenter for another event.
3) The old guy is on 3rd floor. He can't do anything beside touching you if you stay near him for some time.
How did you exactly trigger the kissing scenes? After the heart reached the enemys they looked stunned but i cant do anything with them...