Allen doesn't die. The creators of Invincible comics have kept him alive to drive the story forward and engage the readers with his ongoing adventures.
Allen in these fanfictions is typically a complex character. He has his own goals related to the Millennium Earl and the Akuma, but his feelings for Lenalee add another layer to his personality. He might be hesitant in expressing his emotions at times. Lenalee, on the other hand, is very empathetic. She is able to sense Allen's pain and tries to ease it. Their relationship in the fanfiction is usually based on mutual understanding and a growing, unspoken love that gives both of them something to fight for.
Chen Qiaoen and Alan met and fell in love on the variety show, Daughters in Love. Their relationship had been questioned because of the age difference and Alan's good family background. However, they did not care about public opinion and loved bravely. Alan had made a big difference in Chen Qiaoen's life, making her feel that family was very important. After getting married, Chen Qiaoen also expressed his deep love for Alan and posted a photo of their wedding ring. Their marriage had always been very happy. The couple often appeared on camera together to show their deep love. In Chen Qiaoen's past birthdays, Alan had also held a birthday party for her to show their happiness and love. In general, Qiao En Chen and Allan's relationship was very romantic. They chose to get married in a low-key way and received the blessings of many people.