Drinking bleach
The bloodsucking vines were grown with the help of blood filled with resentment energy and hence, it was only natural that the vines had blood in them.
Fu Jie couldn't remember it clearly because he was panicking but now that he was not in a critical condition anymore, he could recall that in his panicking state, he had indeed swallowed some of the blood from the bloodsucking flower's vine.
His body probably rejected the foreign blood and caused him to cough it all back up.
Fu Jie felt disgusted at the mere thought of drinking all that blood filled with resentment energy.
'HuiXieye, I feel like drinking bleach after this.'
Drinking bleach and thoroughly cleaning up all the residue left behind by that bad blood.