Sure, here's an example of unique content optimized for the keyword 'frisk x chara' using synonyms:
1. The main character
x the fallen human
2. Frisk x Chara
3. The explorer and the wanderer
4. The courageous one and the troubled spirit
5. The challenger x the wanderer
Remember, you can create an infinite number of combinations using different synonyms and variations, but make sure to maintain readability and coherence.