You might remember the meaning of the character 淫 with this easy mnemonic:
Why is that lewd looking man showering droplets (氵) of water onto himself with his claw (爪) like hands? I wish someone would slash (丿) him. I'm just a scholar (士) so I can't do anything.
Using mnemonics to remember the meaning of Chinese characters like has a huge impact on how long to learn Mandarin it takes.