Ti Kuan Yin is a type of oolong tea from China. The name is sometimes also spelled as 'Tie Guan Yin' and literally means 'Iron Goddess'. Because this oolong is tightly rolled during production, one can easily use too much leaves. In the video, below you can see how a small amount of tea fills up the whole brewing vessel once water is added.
Ti Kuan Yin Caffeine
Ti Kuan Yin requires water that's as hot as possible. Thus, the brew will extract more caffeine than the average cup of tea. Though it's still much less than a cup of coffee. If you're sensitive to caffeine, then skip the first brew and let others enjoy it first. Because a large amount of caffeine is extracted during the first brew, you consume much less caffeine starting from the 2nd brew. If you're using a small gaiwan or teapot, this oolong generally lasts for at least 6 brews. The 2-3 brews are the best, so you're not really missing anything.