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