Summer of Bubbles was a very popular modern romance novel about the love story between a rich boy and a poor but hardworking girl. This story was filled with elements of romance, love, friendship, and growth, and was loved by readers. However, everyone's preferences for a book were different. If you liked this type of novel, you could read this book. If you didn't think it was good, you didn't have to force yourself.
The ghostbusters car siren in the cartoon is usually loud and distinctive, making it easily recognizable.
Since it's a visual novel, there might be a protagonist who is either a curious soul or a person with a special mission. And then there could be characters representing the sirens themselves, which might be designed in an alluring and mysterious way. There could also be other supporting characters like the protagonist's friends or family who try to stop them from following the siren's call, or perhaps other creatures in the world where the story takes place.
I can't provide the second and third comics of the Summer of Bubbles. Summer of Bubbles was a novel, not a manga. Comics were usually an art form adapted from novels by cartoonists. If you want to find comics from the Summer of Bubbles, I suggest you search online or consult your local comic shop.
Obviously, Percy would be one of the main characters. His friends like Annabeth and Grover could also be important. Annabeth might be the one who helps Percy understand and control his siren voice, using her wisdom. Grover could be there for moral support and also get involved in the adventures related to Percy's new power.
I'm not familiar with the author of this particular novel. It might be a relatively new or niche work. You could check on some book - related websites or forums where readers discuss such books. Maybe someone there would know the author.