I'm not sure specifically which 'Tunnel Story' Kamina tells without more context. It could be a fictional adventure story set in a tunnel, perhaps involving mystery, danger or discovery.
Since I'm not acquainted with this novel, it's hard to determine the exact theme. But considering the words 'ishq' (love), 'junoon' (passion) and'sakoon' (peace), it might be about how love can involve passion and also lead to a sense of peace. Maybe it shows a journey of love through different emotional states.
Often, these fanfics explore the deep bond between Kamina and Simon. It could be about their adventures together, with a lot of action and the signature over - the - top spirit of Gurren Lagann.
I'm not familiar with 'ishq junoon ishq sakoon complete novel'. However, you could ask in some literature - focused forums or groups where people might be able to give you more information about it, like its plot, characters, and writing style.
Love and adventure could be common themes. Given the nature of the characters, their relationship might be explored in the context of the exciting world they inhabit, with themes of love developing between them as they face various challenges together.
One popular kamina crossover fanfiction might be one where Kamina crosses over into the world of 'Fullmetal Alchemist'. In this story, Kamina's bold personality could contrast with the more reserved characters in 'Fullmetal Alchemist' like Edward and Alphonse. His motivational speeches might inspire the characters in that world to take more risks in their search for the Philosopher's Stone.
One common theme could be adventure. Since they are often in an action - packed anime setting, fanfics might continue their adventures together. Another could be romance, exploring the relationship between Kamina and Yoko in more depth.