The presence of the wild beast and wine cup indicate this figure is of the Dionysian cult. A rock relief in Bisitun, Iran dated 148 B.C. shows a banqueting figured seated on a lion, see H. Luschey, "Bisutun" in Archaologischer Anzeiger, 1974, p. 122, fig. 15, and further comparables are seen in Central Asia, including the statues in the Buddhist sanctuary of Hadda, see P. Bernard, "Au-dèlé du plateu iranien: un hellénisme des confines et ses descendants indo-bactriens" in Le Grand Atlas de l'Art, 1993, p. 119-120.
Given his burly physique and beard, the figure has often been identified as Herakles. Herakles was taught to play the lyre by Linos, and when depicted with the instrument it is often in the context of the Dionysian cult or a formal performance, see "Herakles," J. Boardman and O. Palagia, LIMC, vol. IV, no. 1, pp. 810-816. For further discussion on the popularity of Herakles in Central Asia, see F. B. Flood, "Herakles, the 'Perpetual Acolyte' of the Buddha: some observations on the iconography of Vajrapani in Gandhara Art" in South Asia Archaeology, 5, 1989, p. 17-27.
The Karoshti inscription reads man[n]a sa 20 2 dra 2, which means "Weight stater 22 drakhma 2."