There's a tale, an urban legend, no maybe it can be considered as creepy pasta or even a mixture of those three, that there's a mysterious traveling bard, who go from countries to countries, and whenever and wherever he performed, a disaster is most guarantees to strike the place

Looking at Seraph here, he fit perfectly into this category. Well, the tale or whatever you want to call it doesn't account for his perverted action, as he keeps on hitting on Rafiah (which let me be honest here, I am a milimeter away from knocking his head right now). Muse at least know how to tone down her flirtatious action toward Rean, but Seraph here, I'm sure he will become even wilder should no one is looking, so much for having the name of Seraph

"Why indeed, I should compose a song for all of you, to tell about my tragic back story" [Seraph]

"Talk, and less than 100 words" [Ash]

"Such brutal rejection. You should appreciate my art" [Seraph]

And that flute of him turn into a guitar, and he started singing. Well, since he does help us defeating Motra, I can tolerate his actions. It's annoying but not harmful for the children. Just that

(I see, so that is his story) [Ash]

As he keeps on singing encore part of his so call tragic back story, I manage to summarize few important point

Seraph is both his name and his title. Apparently, alongside the original ten heroes, the angelic whose were power bestow by Goddess of Light, Theia were selected to fight the fallen god on behalf of Goddess of Light. Just like how many of Fallen god follower were from demon race (which then refer to as devil), majority of Theia follower were from Angel race, and thus they're referred to as Angelic, yes the very same angelic transformation those old follower try to achieve. And since most of them were from angel race, a leader was appointed among them, with the first leader of angelic called as Seraph. He later became the angel king and the title of angel king "Seraph" is passed down throughout generation, and now we Seraph here with us, who is still singing. I can't believe this perverted angel is a king 

(Not exactly though... If I'm not mistaken, Angel Kingdom were long destroyed, and the lands for which they stood are now called as the cursed land. It just a dungeon away from The New Headquarters where Saint Louis and Saintess Rumia reside) [Ash]

"And now, for my love song to Rafiah here" [Seraph]

Really. Rafiah is red beet like a tomato right now. Can you stop teasing her like that. The first sentence to his song however

"O Rafiah, who are you really? Why did you Seraph heart?" [Seraph]

"!" "..." [Rafiah] [Ash]

"Stop hitting on her!" [Mira]

"My, but she's beautiful" [Seraph]

"Rafiah, you don't need to answer if you're not comfortable" [Ash]

"True, I can wait for an eternity!" [Seraph]

"Rean, if I make a song for you, will you fall for me?" [Muse]

"Please don't" [Rean]

"Then I'll start composing it now! Master Seraph, please teach me the art of love expression" [Muse]

"Gladly, my little song bird, perhaps we could have a class or two on how to ensnare your boyfriend there" [Seraph]

Muse flirting aside, I'm sure Seraph is actually asking Rafiah about who she really is. Seraph might be perverted, and act like an idiot, but I believe that's just a mask, or maybe just part of his  debauchery personality, but that question about why Rafiah have "Seraph" heart, is a genuine one. One could say, he is literally asking why Rafiah is having Seraph heart. 

"I see. A flower. Calypso, can you make a bouquet of Rose for me?" [Muse]

"Sure do!" [Calypso]

Muse quickly compose a song while throwing those flower to Rean. Well, since they're all distracted with Rean becoming more and more like Rafiah in term of beet red, I approach Seraph

"How come you detect who Rafiah really is?" [Ash]

"Well, let just said it is because of the title Seraph allow me to know a thing or two about other angel, though I must say, her case is definitely a unique one" [Seraph]

"I don't know, she seems awfully reluctant to talk, so please don't press her for answer" [Ash]

"I won't, but that wouldn't stop me from making her fall for me" [Seraph]

"Gust!" [Ash]

"WAIT!" [Seraph]

That actually ticks me off. I mean, Rafiah is older than I am, and it is up to her whether she wanted to date him or not, but making Rafiah uncomfortable with his actions do warrant a ticket for beating

"Ouch...Such barbarian action" [Seraph]

"You get what you deserve" [Ash]

"Rean, you wouldn't do that to me right?" [Muse]

"No I wouldn't" [Rean]

"My husband really is the best" [Muse]

"Someone... help me" [Rean]

"Muse, that's enough. You're scaring him" [Diana]

"Just turn that into an excitement and you're..." [Seraph]

"And don't take advice from him!" [Ash]

I was about to land another gust magic before I remember to ask him another question

"Say, how did you know Motra will cause trouble?" [Ash]

"Again, the title Seraph. Just like the ten heroes, us angelic will have a predisposition to be attracted toward devil, and thus, I travel across the world to do my job. Incidentally, I have met with this old elf few times before, as well as..." [Seraph]

Seraph, once again, transform, no shape shifting into a guy, and

"That is!" [Rumia]

"Oh, you still remember" [Seraph]

"Rumia, is he the traveler that you mentioned before?" [Diana]

"True! Right after you guys help me escape from the head priest and Second queen of Estel clutch, he is the one helping me, before I was introduced to Sir Filvisar and young Saint Louis!" [Rumia]

"What a small world..." [Qis]

Colour me impress. Coincidence? I don't think so

"What next on your plan then?" [Claude]

"Interesting question. Who knows. I might buy a house nearby and help ten heroes here, or I can just continue my journey, helping to stop whatever plan Agnes put into motion" [Seraph]

"Actually, can you stay here just for a while. We need to consider our next step very carefully. At least, until we manage to get any information from Motra, then we can discuss together about this with everyone else" [Diana]

"Not a bad deal. I can ask Rafiah everyday why she have Seraph heart then" [Seraph]

I see. Well, another meeting is ensure I suppose. Let see, based on what happen, I think several key individual will be call, but most importantly

"You twelve, you will join the meeting as well" [Ash]

"!" [Other]