1) Carefree 2) Careless 3) Do-nothing 4) Feckless 5) Flighty 6) Freewheeling 7) Harebrained and unreliable 8) Harum-scarum 9) Hasty 10) Idle 11) Inattentive 12) Loose 13) Out of control 14) Rash 15) Scatterbrained 16) Slaphappy 17) Thoughtless 18) Trigger-happy 19) Unaccountable 20) Uncontrolled 21) Unreliable 1) Careless 2) Feckless 3) Foolish 4) Impetuous 5) Imprudent 6) Reckless 7) Slaphappy 8) Unresponsible 
• (a.) Not to be trusted; unreliable. • (a.) Nor responsible; not liable or able to answer fro consequences; innocent.
[Adjective] Unwilling to take proper responsiblity for your actions.
Ir`re·spon'si·ble adjective [ Prefix ir- not + responsible : confer French irresponsable .] 1. Nor responsible; not liable or able to answer for consequences; innocent. 2. Not to be trusted; unreliable. 
[adj] - showing lack of care for consequences
adjective showing lack of care for consequences; `behaved like an irresponsible idiot`; `hasty and irresponsible action`
said, done, or characterized by a lack of a sense of responsibility: His refusal to work shows him to be completely irresponsible. · not capable of or qualified for responsibility, as due to age, circumstances, or a mental deficiency. · not responsible, answerable, or accountable to higher authority: irresponsible as a monarch.