吸血

吸 = 及 + 口 : Just when Marie Curie (xi) and Yuwen Huaji (及) were on a space trip in front of the space station (Ø1) they encountered an emergency: the failure of their oxygen supply. Their last hope is a hollow mandarin (口) they brought, out of which they suck (吸) their oxygen.

血 = 丶 + 皿 : Mnemonic symbol: blood transfusion.

Xu Xian hurt himself and needs to get a blood transfusion in the elevator's bathroom. He found a petal leaf as donor, which is bleeding droplets into a bowl; Xu Xian gets the blood from the bowl as infusion using some tubes.