Thanks for the chapter!
More details in LN but the chandelier blocks out skills and magic in the room when the candles are lit. Don't know if uses special candles or if any candle will work or whether sealing ability increases rate candles burn. However, since candles are burning spell will either stop once the first candle has burned up it's wax and goes out, or weaken as each candle burns out with spell stopping when last candle goes out.
Vampires are different in this story. Rather than undead corpses they're more like living symbiotic parasites. While most stories have someone bitten or drink blood of a master vampire become a servant vampire with either partial or most of their former intellect intact combined with a craving for blood and degree of bestial behavior. In this story making a new host is forced to drink the vampire's blood allowing the vampire to infest and take over the new host's body making it their own. The body has it's specs increased, allows transformation into vampire form, but unknown whether holy symbols, holy water, or holy magic causes damage similar to that of a normal human or increased damage. In the host's body vampire can take over the host's identity, walk around in sunlight, unknown if able to read or use knowledge or special skills host had, and can still eat, drink, grow old but needs to feed on blood occasionally. Can use anyone as a host but will usually choose a body with good specs (like a muscular warrior over a simple farmer,) that suits the vampires criteria of a suitable host of preferred gender. Whether abilities take time to relearn or power weakened until fully adjust to body after infesting a new host is unknown.
As for the fist technique his is a combination of two styles. The hard style is physical damage caused by a strong hit at the point of impact like getting pummeled from a boxer. Soft style is like the Hyuga clans technique in Naruto where either a special type of energy or ki force has the damage pass through the skin without causing injury until it hits bone or an organ and damaging that severely. Like punching someone in the chest without damaging or bruising the skin but rupturing the heart inside. MC's style combines both. So his fist upon impact is causing blunt force trauma on the skin and smashing it's way inwards while at the same time energy or ki is penetrating to the organs and bone and rupturing them.