肆無忌憚

absolutely unrestrained / unbridled / without the slightest scruple

four (banker's anti-fraud numeral) / unrestrained / wanton / (literary) shop

not to have / no / none / not / to lack / un- / -less

to be jealous of / fear / dread / scruple / to avoid or abstain from / to quit / to give up sth

to be afraid of the consequences / restraining fear

dread / fear / dislike