members of their own family inside the same room, with the likelihood of being discovered, since lust respects no time, locale or circumstance.17 As against AAA’s credible testimony, Colorado’s defenses lack persuasion. While Colorado denied in his testimony that he lived with AAA, such fact was already admitted by the parties during the pretrial. His defense that he was in Osmeña, Dasol at the time of the crime’s commission was even uncorroborated by any other witness. By jurisprudence, denial is an intrinsically weak defense which must be buttressed by strong evidence of non-culpability to merit credibility. Mere denial, without any strong evidence to support it, can scarcely overcome the positive declaration by the child-victim of the identity of the appellant and his involvement in the crime attributed to him.18 Moreover, for the defense of alibi to prosper, two requisites must concur: first, the appellant was at a different place at the time the crime was committed; and second, it was physically impossible for him to be at the crime scene at the time of its commission.19 The defense failed to establish these requisites. On the contrary, Colorado testified that from Osmeña, where he claimed to have lived with an older sister, he could normally reach his parents’ house by a three-hour walk. There were also other means of transportation in these two places,20 which then could have allowed Colorado to travel the distance over a shorter period of time. 1âwphi1 Colorado also questions the weight of Dr. Sanchez’s medico-legal certificate, arguing that AAA’s hymenal lacerations could have resulted from the sexual aggressions allegedly committed against her by DDD and their brother-in-law. Such contention, however, deserves no consideration, given that results of an offended party’s medical examination are merely corroborative in character. As explained by the Court in People v. Balonzo,21 a medical certificate is not necessary to prove the commission of rape, as even a medical examination of the victim is not indispensable in a prosecution for rape. Expert testimony is merely corroborative in character and not essential to conviction. An accused can still be convicted of rape on the basis of the sole testimony of the private complainant.22 Furthermore, laceration of the hymen, even if considered the most telling and irrefutable physical evidence of sexual assault, is not always essential to establish the consummation of the crime of rape. In the context that is used in the RPC, "carnal knowledge," unlike its ordinary connotation of sexual intercourse, does not necessarily require that the vagina be penetrated or that the hymen be ruptured.23 Thus, even granting that AAA’s lacerations were not caused by Colorado, the latter could still be declared guilty of rape, after it was established that he succeeded in having carnal knowledge of the victim. Given the foregoing, the CA did not err in affirming the trial court's conviction of Colorado. The crime is qualified by the victim's minority and her relationship to Colorado, yet the appellate court correctly explained that the imposable penalty is reclusion pe1petua, in lieu of death, taking into account the provisions of Republic Act (R.A.) No. 9346 that prohibit the imposition of death penalty in criminal cases. We however clarify that Colorado shall be ineligible for parole, a requirement under Section 3 of R.A. No. 9346 that was not mentioned in the assailed CA decision and which, must then be rectified by this Decision.24 The civil indemnity, moral damages and exemplary damages, as modified and awarded by the CA, conform to prevailing jurisprudence. WHEREFORE, in view of the foregoing, the Decision dated August 19, 2011 of the Com1 of Appeals in CA-G.R. CR-HC No. 03767 is AFFIRMED with MODIFICATION in that accused-appellant Neil B. Colorado is sentenced to suffer the penalty of reclusion pe1petua, without eligibility for parole. The accused is likewise ordered to pay legal interest on all damages awarded at the legal rate of 6% from the date of finality of this Decision until fully satisfied. SO ORDERED.