Power and transformation could be themes. Given the 'ultimates' and 'oc' in the title, it might be about Hela becoming more powerful or transforming into a new form.
Power dynamics is a common theme. Hela is a very powerful character, so exploring how an OC interacts with her in terms of power, whether they are in awe of her power, or try to gain power from her, is often seen.
Since it's a fanfic, it's difficult to say exactly what it's about without reading it. However, 'ultimates hela' gives the idea that it's centered around a particular interpretation of Hela. The '1610' might be a specific numbering within a series or a reference to a particular setting. The 'x oc' indicates that there is an original character involved. It could be a story of how this original character interacts with Hela in the 'ultimates' context, perhaps they become allies or enemies, or they go through some sort of transformation together.
I'm not entirely sure as the title is rather unclear. It could potentially be a fanfic about a character named Hela with some kind of ultimate form, and perhaps the '3610x oc' might refer to an overclocked (oc) setting related to a system or device within the context of the fanfic. But without reading it, it's just speculation.
Another option is to look for well - known fanfic authors who write in the Marvel universe. Some of them might have dabbled in 'ultimates hela x oc' stories. You can start by checking out the works of authors who have a reputation for writing interesting character relationships. You could also follow fanfic review blogs or YouTube channels that might cover this type of fanfic and recommend some good ones.
The title suggests that the main characters are Hela from the Ultimates in a 1610 context and an original character. Hela is often depicted as a strong and intimidating figure. The original character, which is the creation of the fanfic author, will play a crucial role as well. Their personalities, goals, and backstories will shape the story. It could be that the oc has a unique ability that catches Hela's attention, or perhaps the oc has a mission that involves dealing with Hela in some way.
A common theme is power dynamics. Since Hela is very powerful, exploring how an OC can interact with her in terms of power is often seen. For example, whether the OC is intimidated by her power or tries to gain power from her.
There's also 'Hela and the Mysterious OC'. This one focuses on a more mysterious OC who has some hidden powers. Hela is initially suspicious but then realizes they can achieve great things together. It's full of action scenes where they battle against common enemies in the Avengers' world. The relationship between Hela and the OC evolves in a very engaging way.
One possible theme could be nature and its elements. Since 'brook' is mentioned, it might focus on the beauty and power of nature. The '45 degrees' could add an element of precision or uniqueness to how nature is depicted, like the angle of a ray of sunlight hitting the brook.
One possible theme could be love. The flowers in a box could be a romantic gesture, symbolizing affection between characters. Another theme might be mystery. Maybe the origin of the box of flowers or what's special about the flowers themselves is a mystery. Growth could also be a theme. Just as flowers grow, a character might experience personal growth related to the box of flowers.
One possible theme could be self - discovery. The OC may enter Marie Kanker's world and through their relationship, both characters learn more about themselves. Another theme could be acceptance. They might come from different backgrounds or have different personalities, but they learn to accept each other.