Fraudulent Input Tax Credit triggers GST demand and exclusive penal liability; fake invoice issuers face separate penal provisions. Issuing tax invoices without actual supply is not a 'supply' and does not create tax demand under the DGST Act for the issuer, but the issuer is punishable for issuing invoices without supply. A recipient who fraudulently avails and utilizes ITC without receipt of goods/services is liable to demand and recovery of the ITC with interest and penal action under the fraudulent-ITC provision, with exclusivity of that penalty. If such a recipient passes on the credit by issuing invoices without supply, no tax demand arises for nonexistent outward supply, but penal provisions for issuing fake invoices and wrongful availment/utilization of ITC apply, and others who benefit may also be penalised.