4. How their relationship looks in the show, stage by stage
Stage A — enemies, negotiation, and the first dangerous chemistry
The connection between them doesn't begin with affection, but with political crisis and blood. Lexa and Clarke come at each other out of conflict between Grounders and Skaikru. Already around the Finn story, the connection takes on a crooked emotional line: Lexa says "We are what we are," and then "Then he dies for you," and in one moment it becomes clear that these two are not just standing on opposite sides of a battle line — they are already ideologically dismantling each other. [C4]
Stage B — the alliance, Mount Weather, and attraction through capability
Out of the alliance against Mount Weather, their connection is built through joint work, not through softness. They learn to trust each other's capability. Lexa develops romantic feelings first, Clarke is not there yet, but the chemistry exists and is present. The show emphasizes that the connection between them works also because both are young leaders forced to grow up too fast after loss. [C2][C3][C6]
Stage C — the betrayal
At the Mount Weather point comes the great rupture: Lexa chooses to save her people through a deal with the enemy and leave Clarke and her people exposed. This is one of the main reasons Clexa works so strongly in the fandom — because it isn't clean love. It's love whose room is full of betrayal, mistrust, and prioritizing people over the woman you want. Even much later the canon treats this as the foundational wound of the relationship. [C2][C3]
Stage D — reconciliation at Polis
When they meet again, Clarke is angry. Lexa knows she has to work for every gram of trust she rebuilds. Their relationship in season 3 is much more political, much more intimate, and much more self-aware. Lexa realizes she does not want to continue living by a rule of complete loneliness, and Clarke realizes she is still drawn to a woman who hurt her deeply. [C3][C7]
Stage E — love, sex, death
The romantic line becomes explicit in season 3 around "May we meet again," the kiss, the shared night, and then Lexa's death in "Thirteen," when Titus tries to kill Clarke and hits her instead. This is one of the moments most identified with The 100, both emotionally and culturally. [C3][C4][C11][C12]
Stage F — what remains afterwards
The relationship doesn't really end at Lexa's death, because the canon continues to build her influence on Clarke. Clarke explicitly admits "I loved her." Lexa remains a key character inside the memory, inside the Flame, and inside the later understanding that her betrayal of Clarke was her greatest regret. The Lexa wiki entry explicitly notes that through the relationship with Clarke she no longer sees love as weakness, and that her betrayal of Clarke is a central regret. [C2][C3]